Permit Single Instance of Form

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  - 1
    - Determine running from IDE Hi, I would like to write a line of code which will get used in several debugging points, to look like this.. If app.Mode = IDE then Stop Else End Or if Stopped ended an EXE mode that would be good. Application.StartupPath? Tag: Permit Single Instance of Form Tag: 98209
  - 2
    - Making my winform appear smoothly I have a winform containing a TabControl with multiple TabPages. Each TabPage in turn contains several controls (Labels, TextBoxes ...). Now, when I load my form or switch TabPages, the controls within the form do not appear in a smooth manner, i.e, I see the outlines of the controls first for a fraction of a second and then the form is drawn completely. Is there a way to correct this - to make my form and its controls appear simultaneously? Thanks. Tag: Permit Single Instance of Form Tag: 98208
  - 3
    - Editable Datagridview and dataset Hi, I am using typed dataset to bind to a datagrid. Data set have Id,Name,Date,UserID ,UserName columns. Id is Primary key and UserID is foreign key, so I am not showing it to user. The datagridview has Allow new ,allow delete properties enabled, so that User can enter values in it. I have column autogenerate property false and added ID,Name,UserName columns added at design time. Now question is, when I add a new row in datagridview, after entering value for Name column, when i hit Enter Key, it shows me error that UserID can not be null. Could some one give me idea how to populate UserID value if its not displayed on the datagrid. My goal is to use typed dataset to update data in database using data adaptor. Please guide me how to solve above problem. If the question is confusing, please let me know, I will try to explain further. Thanks in advance. Hiten Tag: Permit Single Instance of Form Tag: 98201
  - 4
    - Dialog and variables Hello, I am looking for some infomation about dialogs and passing / sharring variables best practices. Q1 - What is the best way to pass variables to a dialog form from a main form? Constructor, properties? Q2 - What is the best way to pass the updated variables back to the main form? Properties, Events? Q3 - What is the best way to the main form to be notified when the dialog has its close / save button clicked? ShowDialog, Trigger an event, and have the main form read the public properties and close the dialog? Also any references to docs would be a big help. Thanks, Shawn Tag: Permit Single Instance of Form Tag: 98200
  - 5
    - Able To Have Generic User Controls in .net 2.0? / Winforms and Generics Hey All, I'm wondering if I'm able to have create generic user controls in .net 2.0 much like one can create generic classes. I would like to do this so that I can handle a set a types derived from the same base type within a user control Consider the following scenario: * I create a base user control that contains a generic <ItemType>. * Note: there exists a where clause referencing a specific base type (see code below). * Displays info associated to base class via specific methods. * I derive another user control from this base control with a concrete type * Derived control now displays info associated with the concrete type. Please let me know the following: * If this is possible * If you have done this, what caveats exist * Point me to any online references about the topic Cheers, peter Code ============================= == BASE USER CONTROL == namespace GenericWinformTest { public partial class UserControl1<ItemType> : UserControl where ItemType : Animal, new() { internal Animal itype; public UserControl1() { InitializeComponent(); itype = new ItemType(); } private void talk_Click(object sender, EventArgs e) { this.textBox1.Text = itype.talk(); //talk } }//end class }//end namespace == Derived user control == namespace GenericWinformTest { public partial class dog : UserControl1<type.Dog> { public dog() { InitializeComponent(); } }//end class }//end namespace Tag: Permit Single Instance of Form Tag: 98199
  - 6
    - My.Settings fails in MyApplication_Startup sub (VB.NET 2005) Hi, I am building an application where I use a splash screen when loading the application and I have a setting in My.Settings to control if the splash screen should be shown or not. My problem is that when I try to check this setting in MyApplication_startup sub it seams like the settings are not loaded or something because the setting is set to True but when it reads it from the startup sub its False. Any clue? / Mikael VB.NET 2005 Tag: Permit Single Instance of Form Tag: 98198
  - 7
    - Making a menu disappear upon a toolstriptextbox keypress event? Suppose I have a main menu on my form. after clicking a few menu items with sub menus, you eventually come across a toolstriptextbox. You enter an id number and press the enter button. The keypress event of the toolstriptextbox verifies that enter was pressed, and loads data onto the form based on the id you entered. This all works well aside from one problem... the expanded menu, from the main menu, to the sub menus, to the textbox, are all still on the screen. How can I make the menu collapse or dissappear? Thanks, Mike Tag: Permit Single Instance of Form Tag: 98195
  - 8
    - Why does my datagrid only show from the first tab? I have a page with a DataGridView on a tab control. When that tab is the first tab in the collection, the DataGridView shows up correctly when I bind to my data. However, if I move that tab to not be the first one, the DataGridView never shows up. Moving the tab back results in everything being ok again. I do not understand why this is. Can someone please help me? Thanks. Tag: Permit Single Instance of Form Tag: 98193
  - 9
    - Making Dates with .NET .NET / Making Dates As with any other .NET data structure, you have to create an instance of the DateTime value type before you can use it. DateTime has seven different constructors, although three of them are just duplicates of some others with an extra parameter (a Calendar parameter used for globalization). So really there are only four constructors. Those constructors allow you to initialize a DateTime structure: =B7 To a 64-bit integer value representing a number of ticks =B7 To a specified year, month, and day =B7 To a specified year, month, day, hour, minute, and second =B7 To a specified year, month, day, hour, minute, second, and millisecond For example, this code initializes a DateTime to October 27, 1961 at 8:47 am: C# DateTime MyDate =3D new DateTime(1961, 10, 27, 08, 47, 00); VisualBasic Dim MyDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) .NET Parsing Dates DateTime has two static methods that will parse a string to create a DateTime value. DateTime.Parse attempts to parse a valid date and time out of the string that's passed to it. The string must contain the representation of a date and time in one of the formats described in the DateTimeFormatInfo object that is initialized for the current culture. DateTimeFormatInfo contains information about different date formats like month/year, short and long date/time patterns, weekday and month name abbreviations, and other things that describe the myriad ways that dates and times can be formatted. Parse tries very hard to make sense of the string that's passed to it in order to create a valid DateTime value. It ignores leading and trailing white space, and unrecognized characters if possible, and it fills in missing information with the corresponding current date and time values. Parse will throw a FormatException, though, if it's unable to decipher the string you send to it. Overloaded versions of DateTime.Parse let you specify an object that implements the IFormatProvider provider to describe the expected date format. The other static method that parses strings to make DateTime values is called ParseExact. For this method to succeed, the string that you pass to it must exactly match the format that you specify in the IFormatProvider parameter. The program below illustrates how to use the Parse and ParseExact methods to read dates and times. C# public static void Main() { DateTime MyDate =3D new DateTime(1961, 10, 27, 08, 47, 00); Console.WriteLine(MyDate.ToString()); DateTime NewDate; NewDate =3D DateTime.Parse("10/27/61 08:47"); Console.WriteLine(NewDate.ToString()); NewDate =3D DateTime.Parse("10/1961"); Console.WriteLine(NewDate.ToString()); NewDate =3D DateTime.Parse("27 October 1961 8:47 pm"); Console.WriteLine(NewDate.ToString()); IFormatProvider format =3D new System.Globalization.CultureInfo("fr-FR", true); string[] expectedFormats =3D {"g", "G", "f", "F"}; // This is DD/MM/YYYY format NewDate =3D DateTime.ParseExact( "27/10/1961 08:47:00", expectedFormats, format, System.Globalization.DateTimeStyles.AllowWhiteSpaces); Console.WriteLine("Parsed DD/MM/YY: {0}", NewDate.ToString()); try { NewDate =3D DateTime.ParseExact( "10/27/1961", expectedFormats, format, System.Globalization.DateTimeStyles.AllowWhiteSpaces); Console.WriteLine(NewDate.ToString()); } catch (Exception e) { Console.WriteLine(e.Message); } } VisualBasic Public Shared Sub Main Dim MyDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) Console.WriteLine(MyDate.ToString()) Dim NewDate as DateTime NewDate =3D DateTime.Parse("10/27/61 08:47") Console.WriteLine(NewDate.ToString()) NewDate =3D DateTime.Parse("10/1961") Console.WriteLine(NewDate.ToString()) NewDate =3D DateTime.Parse("27 October 1961 8:47 pm") Console.WriteLine(NewDate.ToString()) Dim format as IFormatProvider =3D _ new System.Globalization.CultureInfo("fr-FR", true) Dim expectedFormats as String() =3D {"g", "G", "f", "F"} ' This is DD/MM/YYYY format NewDate =3D DateTime.ParseExact( _ "27/10/1961 08:47:00", _ expectedFormats, _ format, _ System.Globalization.DateTimeStyles.AllowWhiteSpaces) Console.WriteLine("Parsed DD/MM/YY: {0}", NewDate.ToString()) Try NewDate =3D DateTime.ParseExact( _ "10/27/1961", _ expectedFormats, _ format, _ System.Globalization.DateTimeStyles.AllowWhiteSpaces) Console.WriteLine(NewDate.ToString()) Catch e as Exception Console.WriteLine(e.Message) End Try End Sub The only real tricky part here is the string array passed as the second parameter to ParseExact. This array specifies the formats that the method should try to match when parsing the string. In the code above, I used the general formats (short date with short or long time), and full formats (long date with short or long time). If the string to be parsed doesn't match one of those formats, then ParseExact throws a FormatException exception. See the official documentation for the DateTimeFormatInfo class for a complete list of format characters and patterns. .NET Date Calculations Last updated Jun 16, 2005. The DateTime value type has methods and properties that let you mangle dates in many fun and interesting ways. Properties such as Date, DayOfWeek, Hour, and Ticks let you get information about specific attributes of the DateTime value. All of the properties, by the way, are read only. There is no way to set the Month property on a DateTime value. There are methods that let you add years, months, days, hours, minutes, seconds, and milliseconds to dates; and methods that will convert DateTime values to other date formats like a Windows FileTime or an OLE Automation date. See the official documentation for full information on those methods. DateTime also provides overloads for the comparison operators so you can write things like: if (yourBirthDate < myBirthDate) Console.WriteLine("You're older than I am"); If you're writing in Visual Basic, of course, you don't have access to the overloaded operators so you'd need to use the Compare or CompareTo method, like this: If yourBirthDate.CompareTo(myBirthDate) < 0 Then Console.WriteLine("You're older than I am") End If The overloaded subtraction operator lets you subtract one date from another to obtain the difference in time between the two dates. The returned value is expressed in a TimeSpan: a number of ticks (100 nanosecond time periods). TimeSpan is really just a number that knows how to express itself in terms of days, hours, minutes, seconds, and milliseconds. TimeSpan properties provide you with a way to get the value expressed in these terms (whole days, minutes, and so on), and methods let you initialize a TimeSpan structure from these values. The overloaded TimeSpan constructor lets you initialize a structure with a given number of days, hours, minutes, seconds, and milliseconds. The largest time unit that TimeSpan "knows" about is the day. It's impossible to convert a TimeSpan value to months, for example, because months have differing numbers of days. The same is true for years. So, if you call TimeSpan.ToString to output a value, it will be expressed in days, hours, minutes, seconds, and milliseconds. TimeSpan has two types of properties: those that return whole values, and those that return fractional values. The Days property, for example, gets the number of whole days represented by a TimeSpan value. By contrast, the TotalDays property gets the value expressed as whole and fractional days. So if you have a TimeSpan that represents 25 hours, the value of the Days property would be 1, and the value of the TotalDays property would be 1.04167 (that is, 1 and 1/24 days). There are similar properties for hours, minutes, seconds, and milliseconds. Of course, since TimeSpan is "just a number," you can use the standard comparison operators to see which of two values is larger or smaller, and you can use the standard operators to add and subtract TimeSpan values. TimeSpan, though, is not terribly useful all by itself. It's really intended to be used in conjunction with DateTime values. The difference between two dates, as pointed out above, is expressed in a TimeSpan. This code subtracts one date from another to get the time elapsed between them. C# DateTime BirthDate =3D new DateTime(1961, 10, 27, 08, 47, 00); DateTime Today =3D DateTime.Now; TimeSpan Age =3D Today - BirthDate; VisualBasic Dim BirthDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) Dim Today as DateTime =3D DateTime.Now Dim Age as TimeSpan =3D Today.Subtract(BirthDate) You should note that in the second line of code I got the current date and time by accessing the static DateTime.Now property. If you initialize the BirthDate variable in the code above with your own birth date, then the Age variable will represent your current age. If you then want to see what the date will be when you're twice as old as you are right now, you simply add the calculated Age value to Today, like this: C# DateTime ALongTimeFromNow =3D Today + Age; Console.WriteLine(ALongTimeFromNow.ToString()); VisualBasic Dim ALongTimeFromNow as DateTime =3D Today.Add(Age) Console.WriteLine(ALongTimeFromNow.ToString()) .NET Official Documentation Last updated Jun 16, 2005. The DateTime and TimeSpan topics in the MSDN .NET Reference fully describe the methods and properties of these objects, and give some very good examples of using them in typical situations. If you need to work with other calendars or multiple cultures, be sure to check the references for Calendar, DateTimeStyles, and DateTimeFormatInfo in the System.Globalization namespace. http://www.imc.org/rfc2822 .NET Properties Last updated Jul 27, 2005. I had originally planned to duplicate all of the DateTime properties and methods in W3CDateTime. As I got into it, though, I started thinking that I was needlessly duplicating a lot of effort. This is something of a judgement call, I'll admit. However, it seemed silly to implement the Hour property when I could just as easily call get the Hour property on W3CDateTime.DateTime. That is, these two calls would be identical: hour =3D myDate.Hour; hour =3D myDate.DateTime.Hour; In most cases, I avoided duplicating effort. The result is that I only implemented a handful of properties for W3CDateTime, all of them static. The properties that I implemented are: LocalUtcOffset returns the offset between the local time (on the computer that's running the program) and UTC time. MaxValue returns a W3CDateTime that represents the maximum value that can be represented. This value is expressed in UTC time. MinValue returns a W3CDateTime that represents the minimum value that can be represented. This value is expressed in UTC time. Now returns the current local time, expressed in the local time zone. Today returns the current date, expressed in the local time zone. The time portion is set to 00:00:00. UtcNow returns the current time, expressed in UTC time. All of these are static properties. With the exception LocalUtcOffset, all of these properties are duplicates of properties implemented by System.DateTime. The duplication seemed reasonable in these cases. New Methods I needed the ability to do comparisons on W3CDateTime values, and also to add days, months, years, etc. I also needed to subtract two dates to determine the number of days or hours between them. System.DateTime implements all of this functionality, of course, but it becomes difficult to use. For example, if I wanted to add days to a W3CDateTime to get another value, I would have to write: myDateTime =3D new W3CDateTime(myDateTime.DateTime.AddDays(5), myDateTime.UtcOffset); By creating an AddDays method, I'm now able to write: myDateTime =3D myDateTime.AddDays(5); Subtracting two dates was a little trickier in that I had to be sure to use the UtcTime property. Otherwise, subtracting dates from two different time zones would produce erroneous results. For those reasons, I implemented the AddYears, AddHours, and similar methods, as well as both overloads of the Subtract method that are supported by System.DateTime. For comparisons, I implemented a static Compare method as well as the IComparable.CompareTo method. For equality testing, I implemented Equals and GetHashCode as outlined in the SDK article Implementing the Equals Method. Finally, I implemented two conversion methods: ToLocalTime and ToUniversalTime. These are similar to the methods implemented by System.DateTime, except that I added an overload that will convert the value to any given timezone offset. Tag: Permit Single Instance of Form Tag: 98188
  - 10
    - Making Dates with .NET .NET / Making Dates As with any other .NET data structure, you have to create an instance of the DateTime value type before you can use it. DateTime has seven different constructors, although three of them are just duplicates of some others with an extra parameter (a Calendar parameter used for globalization). So really there are only four constructors. Those constructors allow you to initialize a DateTime structure: =B7 To a 64-bit integer value representing a number of ticks =B7 To a specified year, month, and day =B7 To a specified year, month, day, hour, minute, and second =B7 To a specified year, month, day, hour, minute, second, and millisecond For example, this code initializes a DateTime to October 27, 1961 at 8:47 am: C# DateTime MyDate =3D new DateTime(1961, 10, 27, 08, 47, 00); VisualBasic Dim MyDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) .NET Parsing Dates DateTime has two static methods that will parse a string to create a DateTime value. DateTime.Parse attempts to parse a valid date and time out of the string that's passed to it. The string must contain the representation of a date and time in one of the formats described in the DateTimeFormatInfo object that is initialized for the current culture. DateTimeFormatInfo contains information about different date formats like month/year, short and long date/time patterns, weekday and month name abbreviations, and other things that describe the myriad ways that dates and times can be formatted. Parse tries very hard to make sense of the string that's passed to it in order to create a valid DateTime value. It ignores leading and trailing white space, and unrecognized characters if possible, and it fills in missing information with the corresponding current date and time values. Parse will throw a FormatException, though, if it's unable to decipher the string you send to it. Overloaded versions of DateTime.Parse let you specify an object that implements the IFormatProvider provider to describe the expected date format. The other static method that parses strings to make DateTime values is called ParseExact. For this method to succeed, the string that you pass to it must exactly match the format that you specify in the IFormatProvider parameter. The program below illustrates how to use the Parse and ParseExact methods to read dates and times. C# public static void Main() { DateTime MyDate =3D new DateTime(1961, 10, 27, 08, 47, 00); Console.WriteLine(MyDate.ToString()); DateTime NewDate; NewDate =3D DateTime.Parse("10/27/61 08:47"); Console.WriteLine(NewDate.ToString()); NewDate =3D DateTime.Parse("10/1961"); Console.WriteLine(NewDate.ToString()); NewDate =3D DateTime.Parse("27 October 1961 8:47 pm"); Console.WriteLine(NewDate.ToString()); IFormatProvider format =3D new System.Globalization.CultureInfo("fr-FR", true); string[] expectedFormats =3D {"g", "G", "f", "F"}; // This is DD/MM/YYYY format NewDate =3D DateTime.ParseExact( "27/10/1961 08:47:00", expectedFormats, format, System.Globalization.DateTimeStyles.AllowWhiteSpaces); Console.WriteLine("Parsed DD/MM/YY: {0}", NewDate.ToString()); try { NewDate =3D DateTime.ParseExact( "10/27/1961", expectedFormats, format, System.Globalization.DateTimeStyles.AllowWhiteSpaces); Console.WriteLine(NewDate.ToString()); } catch (Exception e) { Console.WriteLine(e.Message); } } VisualBasic Public Shared Sub Main Dim MyDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) Console.WriteLine(MyDate.ToString()) Dim NewDate as DateTime NewDate =3D DateTime.Parse("10/27/61 08:47") Console.WriteLine(NewDate.ToString()) NewDate =3D DateTime.Parse("10/1961") Console.WriteLine(NewDate.ToString()) NewDate =3D DateTime.Parse("27 October 1961 8:47 pm") Console.WriteLine(NewDate.ToString()) Dim format as IFormatProvider =3D _ new System.Globalization.CultureInfo("fr-FR", true) Dim expectedFormats as String() =3D {"g", "G", "f", "F"} ' This is DD/MM/YYYY format NewDate =3D DateTime.ParseExact( _ "27/10/1961 08:47:00", _ expectedFormats, _ format, _ System.Globalization.DateTimeStyles.AllowWhiteSpaces) Console.WriteLine("Parsed DD/MM/YY: {0}", NewDate.ToString()) Try NewDate =3D DateTime.ParseExact( _ "10/27/1961", _ expectedFormats, _ format, _ System.Globalization.DateTimeStyles.AllowWhiteSpaces) Console.WriteLine(NewDate.ToString()) Catch e as Exception Console.WriteLine(e.Message) End Try End Sub The only real tricky part here is the string array passed as the second parameter to ParseExact. This array specifies the formats that the method should try to match when parsing the string. In the code above, I used the general formats (short date with short or long time), and full formats (long date with short or long time). If the string to be parsed doesn't match one of those formats, then ParseExact throws a FormatException exception. See the official documentation for the DateTimeFormatInfo class for a complete list of format characters and patterns. .NET Date Calculations Last updated Jun 16, 2005. The DateTime value type has methods and properties that let you mangle dates in many fun and interesting ways. Properties such as Date, DayOfWeek, Hour, and Ticks let you get information about specific attributes of the DateTime value. All of the properties, by the way, are read only. There is no way to set the Month property on a DateTime value. There are methods that let you add years, months, days, hours, minutes, seconds, and milliseconds to dates; and methods that will convert DateTime values to other date formats like a Windows FileTime or an OLE Automation date. See the official documentation for full information on those methods. DateTime also provides overloads for the comparison operators so you can write things like: if (yourBirthDate < myBirthDate) Console.WriteLine("You're older than I am"); If you're writing in Visual Basic, of course, you don't have access to the overloaded operators so you'd need to use the Compare or CompareTo method, like this: If yourBirthDate.CompareTo(myBirthDate) < 0 Then Console.WriteLine("You're older than I am") End If The overloaded subtraction operator lets you subtract one date from another to obtain the difference in time between the two dates. The returned value is expressed in a TimeSpan: a number of ticks (100 nanosecond time periods). TimeSpan is really just a number that knows how to express itself in terms of days, hours, minutes, seconds, and milliseconds. TimeSpan properties provide you with a way to get the value expressed in these terms (whole days, minutes, and so on), and methods let you initialize a TimeSpan structure from these values. The overloaded TimeSpan constructor lets you initialize a structure with a given number of days, hours, minutes, seconds, and milliseconds. The largest time unit that TimeSpan "knows" about is the day. It's impossible to convert a TimeSpan value to months, for example, because months have differing numbers of days. The same is true for years. So, if you call TimeSpan.ToString to output a value, it will be expressed in days, hours, minutes, seconds, and milliseconds. TimeSpan has two types of properties: those that return whole values, and those that return fractional values. The Days property, for example, gets the number of whole days represented by a TimeSpan value. By contrast, the TotalDays property gets the value expressed as whole and fractional days. So if you have a TimeSpan that represents 25 hours, the value of the Days property would be 1, and the value of the TotalDays property would be 1.04167 (that is, 1 and 1/24 days). There are similar properties for hours, minutes, seconds, and milliseconds. Of course, since TimeSpan is "just a number," you can use the standard comparison operators to see which of two values is larger or smaller, and you can use the standard operators to add and subtract TimeSpan values. TimeSpan, though, is not terribly useful all by itself. It's really intended to be used in conjunction with DateTime values. The difference between two dates, as pointed out above, is expressed in a TimeSpan. This code subtracts one date from another to get the time elapsed between them. C# DateTime BirthDate =3D new DateTime(1961, 10, 27, 08, 47, 00); DateTime Today =3D DateTime.Now; TimeSpan Age =3D Today - BirthDate; VisualBasic Dim BirthDate as DateTime =3D new DateTime(1961, 10, 27, 08, 47, 00) Dim Today as DateTime =3D DateTime.Now Dim Age as TimeSpan =3D Today.Subtract(BirthDate) You should note that in the second line of code I got the current date and time by accessing the static DateTime.Now property. If you initialize the BirthDate variable in the code above with your own birth date, then the Age variable will represent your current age. If you then want to see what the date will be when you're twice as old as you are right now, you simply add the calculated Age value to Today, like this: C# DateTime ALongTimeFromNow =3D Today + Age; Console.WriteLine(ALongTimeFromNow.ToString()); VisualBasic Dim ALongTimeFromNow as DateTime =3D Today.Add(Age) Console.WriteLine(ALongTimeFromNow.ToString()) .NET Official Documentation Last updated Jun 16, 2005. The DateTime and TimeSpan topics in the MSDN .NET Reference fully describe the methods and properties of these objects, and give some very good examples of using them in typical situations. If you need to work with other calendars or multiple cultures, be sure to check the references for Calendar, DateTimeStyles, and DateTimeFormatInfo in the System.Globalization namespace. http://www.imc.org/rfc2822 .NET Properties Last updated Jul 27, 2005. I had originally planned to duplicate all of the DateTime properties and methods in W3CDateTime. As I got into it, though, I started thinking that I was needlessly duplicating a lot of effort. This is something of a judgement call, I'll admit. However, it seemed silly to implement the Hour property when I could just as easily call get the Hour property on W3CDateTime.DateTime. That is, these two calls would be identical: hour =3D myDate.Hour; hour =3D myDate.DateTime.Hour; In most cases, I avoided duplicating effort. The result is that I only implemented a handful of properties for W3CDateTime, all of them static. The properties that I implemented are: LocalUtcOffset returns the offset between the local time (on the computer that's running the program) and UTC time. MaxValue returns a W3CDateTime that represents the maximum value that can be represented. This value is expressed in UTC time. MinValue returns a W3CDateTime that represents the minimum value that can be represented. This value is expressed in UTC time. Now returns the current local time, expressed in the local time zone. Today returns the current date, expressed in the local time zone. The time portion is set to 00:00:00. UtcNow returns the current time, expressed in UTC time. All of these are static properties. With the exception LocalUtcOffset, all of these properties are duplicates of properties implemented by System.DateTime. The duplication seemed reasonable in these cases. New Methods I needed the ability to do comparisons on W3CDateTime values, and also to add days, months, years, etc. I also needed to subtract two dates to determine the number of days or hours between them. System.DateTime implements all of this functionality, of course, but it becomes difficult to use. For example, if I wanted to add days to a W3CDateTime to get another value, I would have to write: myDateTime =3D new W3CDateTime(myDateTime.DateTime.AddDays(5), myDateTime.UtcOffset); By creating an AddDays method, I'm now able to write: myDateTime =3D myDateTime.AddDays(5); Subtracting two dates was a little trickier in that I had to be sure to use the UtcTime property. Otherwise, subtracting dates from two different time zones would produce erroneous results. For those reasons, I implemented the AddYears, AddHours, and similar methods, as well as both overloads of the Subtract method that are supported by System.DateTime. For comparisons, I implemented a static Compare method as well as the IComparable.CompareTo method. For equality testing, I implemented Equals and GetHashCode as outlined in the SDK article Implementing the Equals Method. Finally, I implemented two conversion methods: ToLocalTime and ToUniversalTime. These are similar to the methods implemented by System.DateTime, except that I added an overload that will convert the value to any given timezone offset. Tag: Permit Single Instance of Form Tag: 98187
  - 11
    - Drag and Drop between treeviews on TWO forms in MDI... Hi, I have two child forms in my MDI application. They both have treeviews with different data but in teh same format (fund, tran type) I want to be able to drag a node from one to the other but it seems it only works between one or more tree views on the same form, not different forms. How can I either enable drag and drop between two forms from treeview to treeview or maybe use a copy/paste option? thanks for any help. Philip Tag: Permit Single Instance of Form Tag: 98184
  - 12
    - Referencing forms? I am trying to understand how to work with multiple forms. To aid in my understanding, I created a project with two forms each with a single button. When Form1's button is clicked, the form is hiddend via Me.Hide and Form2 is shown using ShowDialog. When Form2's button is clicked I want to close Form2 and show Form1. My stumbling block is how to reference Form1. I tried Form1.Show but this does not work. What am I doing wrong? Any help is appreciated. -Thanks Tag: Permit Single Instance of Form Tag: 98183
  - 13
    - Datagrid w/ DataSet: Mouseover in treeview? I am using a Datagrid with a DataSet which contains multiple tables. The Datagrid shows these tables in a tree-like matter. Once the mouse is moved over the tablelinks of the tree the cursor changes to symbol "hand" for signalling that by clicking it is possible to switch to the column-/ row-view of the selected table. This is standard behaviour. Question: While browsing in tree view, is there a possibillity for a mouseover that determines the tablename of the tablelink where the mousepointer is positioned? e.g. Tree shows links as: Table1 Table2 Table3 Table4 Now if mouse is put over Table3-link I want to know this. There is no DataGrid.HitTestType for this issue. It is Type "none". Tag: Permit Single Instance of Form Tag: 98179
  - 14
    - How to convert Message.LParam pointer to CREATESTRUCT to an object I'm capturing WM_CREATE messages by overriding WndProc in C#/.NET. How do I then convert the CREATESTRUCT* that GetLParam() would return to an object that I can use in my code ? protected override void WndProc(ref System.Windows.Forms.Message m) { if (m.Msg == Convert.ToInt32(WindowsMessages.WM_CREATE)) { StringBuilder text = new StringBuilder("msg = " + m.Msg.ToString() + "wParam=" + m.WParam.ToString() + ", lparam=" + m.LParam.ToString()); // call m.GetLParam() - gets a pointer to CREATESTRUCT; } base.WndProc (ref m); } Tag: Permit Single Instance of Form Tag: 98176
  - 15
    - PrintPreviwDialog Force Close I am working on a medical application that has to time out. When this occurs, the user may have a modal PrintPreviewDialog up, which I need to close. The CommonDialogs are odd beasts. Anyone know how to force one to close? Tag: Permit Single Instance of Form Tag: 98175
  - 16
    - Application has generated an exception that could not be handled I have an application developed by .net framework 1.0 , the application works fine on my development machine , but on the non-development machine (the customer machine) the application sometime crashes giving this error message , note that i handeled the unhandled exceptions in my application and that also there is no a particualr scenario that produces this exception. So does anyone have any ideas about what could be the reason for this exception , please help me because am stuck in this problem for more than a month now. I would Like to add that the application runs and that this exception appears while using the application. Thanks for the help in advance Tag: Permit Single Instance of Form Tag: 98174
  - 17
    - Accessing an IFrame's document. Hi I am writing an test automation library in C#, .NET 2005 using "Microsoft.mshtml". All was going well in testing the web application until I can go to a page containing an IFrame element. I do not know how to access the Document associated with the frame. I can get the IHTMLFrameElement easily enough,but I cannot see contentDocument member in this element class. I m only getting contentWindow that too is throwing an InvalidCastException. I facing this problem for every page containing an iFrame. Thanx... Mayank Jain Tag: Permit Single Instance of Form Tag: 98169
  - 18
    - How to set ListView scroll info? I have a listview whose contents are constantly being refreshed. When a refresh occurs, I delete all the items and add back. I want to maintain the scroll position before deleting all the items, and then want to restore it once the items are added back. I'm using P/Invoke Get/SetScrollInfo to get and restore the scroll information. GetScrollInfo is working fine - it returns expected information. SetScrollInfo has no effect - the scroll positions are unchanged (both horz and vert are 0). I also tried Get/SetScrollPos - no luck there, either. Is this the correct way to do this? Anyone know what might be wrong? Here's some of my code: private void RefreshList() { User32.SCROLLINFO hsi = User32.GetScrollInfo((uint) MyListView.Handle.ToInt32(), Constants.SB_HORZ); User32.SCROLLINFO vsi = User32.GetScrollInfo((uint) MyListView.Handle.ToInt32(), Constants.SB_VERT); MyListView.BeginUpdate(); MyListView.Items.Clear(); // Add new items here... User32.SetScrollInfo((uint)MyListView.Handle.ToInt32(), Constants.SB_HORZ, false, hsi); User32.SetScrollInfo((uint)MyListView.Handle.ToInt32(), Constants.SB_VERT, false, vsi); MyListView.EndUpdate(); } public class Constants { public const int SB_HORZ = 0; public const int SB_VERT = 1; public const int SB_CTL = 2; public const int SB_BOTH = 4; public const int SIF_RANGE = 0x0001; public const int SIF_PAGE = 0x0002; public const int SIF_POS = 0x0004; public const int SIF_DISABLENOSCROLL = 0x0008; public const int SIF_TRACKPOS = 0x0010; public const int SIF_ALL = (SIF_RANGE | SIF_PAGE | SIF_POS | SIF_TRACKPOS); } public class User32 { [StructLayout(LayoutKind.Sequential)] public struct SCROLLINFO { public UInt32 cbSize; public UInt32 fMask; public Int32 nMin; public Int32 nMax; public UInt32 nPage; public Int32 nPos; public Int32 nTrackPos; } [DllImport("user32.dll", EntryPoint = "GetScrollInfo", SetLastError = true)] private static extern int GetScrollInfoWnd(uint hWnd, int nBar, ref SCROLLINFO si); public static SCROLLINFO GetScrollInfo(uint hWnd, int nBar) { SCROLLINFO si = new SCROLLINFO(); si.cbSize = (uint) System.Runtime.InteropServices.Marshal.SizeOf(si); si.fMask = Constants.SIF_ALL; // also tried si.fMask = Constants.SIF_PAGE | Constants.SIF_POS | Constants.SIF_RANGE GetScrollInfoWnd(hWnd, nBar, ref si); // returns correct data return si; } [DllImport("user32.dll", EntryPoint = "SetScrollInfo", SetLastError = true)] private static extern int SetScrollInfoWnd(uint hWnd, int nBar, bool bRedraw, ref SCROLLINFO si); public static int SetScrollInfo(uint hWnd, int nBar, bool bRedraw, SCROLLINFO si) { int rc = SetScrollInfoWnd(hWnd, nBar, bRedraw, ref si); return rc; // return is 0 - presumably previous scroll position } } Thanks -- Michael Salamone [eMVP] Entrek Software, Inc. www.entrek.com Tag: Permit Single Instance of Form Tag: 98164
  - 19
    - How do I show a visually inherited form? I just started working with inherited forms and am being befuddled with how to show the inherited form. As a test, I designed Form1 with a single button on it and added an inherited form that inherits from Form1. When my application starts, I would like to have both forms show at the same time. How can this be done? I tried placing the following code in the Form1_Load event: Dim form2 As New InheritedForm form2.Show() but this gives me the following error: An unhandled exception of type 'System.ComponentModel.Win32Exception' occurred in system.windows.forms.dll Additional information: Error creating window handle. What am I doing incorrectly that is generating this error? -Thanks Tag: Permit Single Instance of Form Tag: 98158
  - 20
    - Recursion in CreateChildControls In my custom control I have overriden CreateChildControls and the first few lines look like this. protected override void CreateChildControls() { Debug.WriteLine("CreateChildControls", "FeatureList"); Controls.Clear(); .. } what I am seeing is that the Controls.Clear line indirectly calls CreateChildControls (the call is through a Get on the Controls collection from the stack). Although the controls end up being right, they are created twice which is hardly efficient. What do I need to do to stop this happening? Iain -- Iain Downs (DirectShow MVP) Commercial Software Therapist www.idcl.co.uk Tag: Permit Single Instance of Form Tag: 98155
  - 21
    - MonthCalendar - display problem when selecting a date range I am using VS 2005, .net Framework 2.0 When I select a range of dates, the selected dates are whited out except for 1/2 of the first and last date (these are highlighted in blue). This issue also occurs if I select a date and then use the year spinner button to go back a year. To track the issue, I started a new windows forms project, on the default form1 I added a monthcalendar, I have not changed any properties on the form or control. My theme set to default Windows XP. any ideas? Thanks -- Gord Tag: Permit Single Instance of Form Tag: 98153
  - 22
    - Compare dataset values I built a windows services application which should run 24 X 7, and the system picks user defined parameter to perform scheduled work. My scheduler will pick users settings (dataset) from database to perform task; In order to keep my scheduler perform task when users setting changed, I create a thread timer to retrieve schedule settings from database and compare with my current running schedule task. If settings changed, (by comparing each row values), the scheduler will stop current processes and re-schedule new task. My question is, instead of comparing dataset by rows, is there any other better or efficient way, and how should it be? Tag: Permit Single Instance of Form Tag: 98150
  - 23
    - Scrollbar problem with RichTextBox Hi, I don't know if this is a bug or is it just me not finding the solution? In VC# 2005 (running Windows2000) I have a multiline RichTextBox with ScrollBars set to "Both", but not forced. So I want to see no scrollbars at the beginning, and then, while filling up the Box with text, they should appear with a proportional thumb as usual. When deleting some text, the bars should disappear again. Well, instead of that, I get the following: As long as I don't resize the window, I can type in text without problems, but no scrollbars appear when arriving at the bottom or at the right. Only when I then resize the window (might be by only 2 mm), the scrollbars appear as they should, and from then on, everything works fine untill I close the app. But when I resize before reaching the margins, then dysfunctional scrollbars appear, with nonproportional thumbs, and the stay there until the text reaches the margins, for then to turn to normal scrollbars for the rest of the app's life. This behavior is independently for the horizontal and vertical scrollbar, each of them waiting text to come to its corresponding margin (right or bottom) before starting to work as it should, provided a resize has been done once. Quite annoying, what am I doing wrong? Thanks for any help Joe Tag: Permit Single Instance of Form Tag: 98149
  - 24
    - TextBox AutoScale in VS 2005 designer I've recently moved to VS 2005 and .NET Framework 2.0 (from VS .NET 2003 and .NET Framework 1.1). And I have a trivial problem in designer: 1) I create a new project with default settings (C# Windows Application). OK. 2) And on the main form I put a TextBox. I set its width to 100 pixels. OK so far. 3) Now I change TextBox font to Courier New, 12pt, bold. OK. 4) I want to set the TextBox'es height to 24 pixels. And I can't. It sets its height back to 26 pixels. 5) So I want to change the property called AutoSize. TextBox inherits such a property from TextBoxBase. But it is TextBoxBase's property, not TextBox'es, so the property window doesn't show it. 6) So I modify the code generated by designer, I add a line: textbox.AutoSize = false; and change height to 24. OK, it works for a while. But when designer makes any changes to code, it removes the line above that I added and returns back to 26 pixels. Now what I can do is change the AutoSize property and Height somewhere else in code, where designer won't mess up. But: 1) It's not optimal to change the control's size twice: once when it is created with the size forced by designer, and then again change the size to what I want it to be 2) When I change it in code I lose the possibility to view visually how the final effect will be, because designer will show something different from what will be set during runtime. I want to layout controls in designer. I don't want to set all the sizes and positions at runtime in code without preview, because it's too much work with over 30 controls. And if I can't do it in designer, then VS 2005 is a useless tool. I can write code in notepad. 3) I had no such problem in .NET 1.1 and Visual Studio .NET 2003 4) I have no problem with other controls, such as Label, which has a property AutoSize on its own (not inherited) and I can change that property in designer's property window, and all works fine. Any ideas how can I turn off TextBox'es AutoSize property in designer? Thanks in advance, Agata Staniak Tag: Permit Single Instance of Form Tag: 98147
  - 25
    - Trouble with BindingSource I've gone through a few demos and walkthroughs trying to become familiar with the new binding in vs2005. I'm having some success, but not every time. I've create a dataset with the datasource configuration wizard. I have 3 tables in this dataset (expense, category, and type). I drag each table onto a separate form. Visual studio creates a datagridview and binding navigator on each form. When executed, the grids on each form populate correctly. The problem is that one of the tables doesn't get updated when I press save, the other two save correctly. I'm not writing any code, just using the autogenerated code that VS writes: Private Sub ExpenseBindingNavigatorSaveItem_Click(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles ExpenseBindingNavigatorSaveItem.Click Me.Validate() Me.ExpenseBindingSource.EndEdit() Me.ExpenseTableAdapter.Update(Me.ExpenseDataSet.expense) End Sub I can't figure out what is different about the expense table/grid that is causing it to not update. There are no errors generated. If I inspect the dataset in the debugger after I make changes in the grid, the dataset appears to get updated. I therefore believe it has something to do with the BindingSource or TableAdapter. The changes never make it from the dataset to the database (an access db). Joel Tag: Permit Single Instance of Form Tag: 98146
- Next
  - 1
    - Catch Exception problem.... How to catch the windows exception that shows a window with the name of the executable program and a messege saying : "[Program] has encounterd a problem and needs to close. We are sorry for the inconvenience", and three buttons, "Debug", "Send Error Report" and "Don't Send", in a dotnet applicacion, if its posible, of course... Tag: Permit Single Instance of Form Tag: 98142
  - 2
    - How to protect ADO.NET connection string under WindowsForms? Hello I build WindowsForm application, that use MS Access database. I wish to protect AccessDB password that I use in connection string. Application will be used by final users and customers. I understand that .NET framework application is easy to decompile and trace it's variables. So how to hide or protect connection string from easy disrupt, and reading DB password. Thanks MilanB Tag: Permit Single Instance of Form Tag: 98137
  - 3
    - how ?? I want to run one perticular executable from Harddisk (installed lincenced application ) so there is entry of path where that application is installed NOW HOW CAN I LOCATE THAT PATH ??(USING VB.NET) Tag: Permit Single Instance of Form Tag: 98135
  - 4
    - Error clicking List View Columns Headers (Application Verifier: He Hi All, Error while sorting ListView Items. While clicking the columns headers in ListView, an Access Violation Exception is thrown. Not always but sometimes. The Error was reported when testing the application using Application Verifier under Heap section... Thanks in Advance, Karthik Tag: Permit Single Instance of Form Tag: 98133
  - 5
    - DatagridView only add rows no edit existing Hello I need a DatagridView with the option of read-only for existing record but that I can insert new records I try with this.dataGridView1.ReadOnly = false; this.dataGridView1.AllowUserToAddRows = true; this.dataGridView1.AllowUserToDeleteRows = false; but the problem is that the user can update existing records and I want only able to insert new ones. if I use this.dataGridView1.ReadOnly = true; the user have a new record but can edit the information a the new one Please I think the solution is very simple but I have invest a lot of time with different combinations without any positive result please help MajorTom Tag: Permit Single Instance of Form Tag: 98131
  - 6
    - Cursor on ListView Hi I have a form in which there is a treeview alongside a listview. Now I have certain conditions when the Listview control is disabled. When this happens I would want the Cursor to be of type "NO" only when the mouse is over the ListView. It should be default over the other controls on the form. I have tried many things but nothing seems to work. I am able to set the Cursor to No when the Listview is disabled ...but the cursor does not change to default if I leave the Listview control... The mouse events dont seem to help either. Next I tried using the Cursor.draw(graphics, rectangle) method with the rectangle being the size of the Listview control. I thought this would limit the No cursor only within this rectangle. But Nope did not work! Even if i change the cursor property to anything else from the designer for the listview or even the form..it doesnt seem to work... what am i missing??????? appreciate all responses Thanks, Vinit Tag: Permit Single Instance of Form Tag: 98130
  - 7
    - Print To File hangs when cancelled. When you cancel the status window when printing to a file, the status window hangs and cannot be closed ---you must go to the task manager to End the window session in order to close the window. This is a demonstrable problem in Net Framework 1.1 by using the code below. I could not find any solution to this problem in Knowledge Base. **** StringReader streamToPrint = new StringReader (textArea.Text); //Assumes the default printer TextPrintDocument pd = new TextPrintDocument(streamToPrint,textArea.Font); if (storedPageSettings != null) { pd.DefaultPageSettings = storedPageSettings ; } PrintDialog dlg = new PrintDialog() ; dlg.Document = pd; DialogResult result = dlg.ShowDialog(); try { if (result == DialogResult.OK) { pd.Print(); } } catch( Exception ex ) { Console.WriteLine(ex); dlg.Dispose(); } Tag: Permit Single Instance of Form Tag: 98129
  - 8
    - TypeConverters IsValid method not getting called I have a TypeConverter derived from StringConverter in which I have overridden GetStandardValuesSupported GetStandardValues GetStandardValuesExclusive IsValid. Now, initially when I wrote this I did not have an IsValid method and therefore even if I entered an invalid value for the property on which my typeconverter is applied to it would accept it. After I added the IsValid method, I expected this behavior to change but when I run it under the debugger the IsValid method is not getting called at all. Any idea what is happening here? Thanks. Tag: Permit Single Instance of Form Tag: 98127
  - 9
    - Serializing TreeView and DataGridView controls states Hello All, First of all thanks in advance to everyone who will try to help me. I have Form with TreeView control and DataGridView control. Each TreeNode has its own rows and due to I am placing rows to ArrayList and store it in tag of TreeNode like this: // dgv - DataGridView visible within whole class private void treeView1_AfterSelect(object sender, TreeViewEventArgs e) { dgv.Rows.Clear(); dgv.Columns.Clear(); DataGridViewCheckBoxColumn ins = new DataGridViewCheckBoxColumn(); ins.Name = "Insert"; ins.HeaderText = "Insert; ins.Width = 90; DataGridViewTextBoxColumn itemName = new DataGridViewTextBoxColumn(); itemName.HeaderText = "Item name"; itemName.Name = "itemName"; itemName.Width = (dgv.Width - ins.Width - 43) / 2; DataGridViewTextBoxColumn itemValue = new DataGridViewTextBoxColumn(); itemValue.HeaderText = "Item Value"; itemValue.Name = "itemValue"; itemValue.Width = (dgv.Width - ins.Width - 43) / 2; DataGridViewComboBoxColumn mdfLink = new DataGridViewComboBoxColumn(); mdfLink.Name = "mdfLink"; mdfLink.HeaderText = "MDF Link"; mdfLink.Width = (dgv.Width - 80) / 6; mdfLink.DropDownWidth = mdfLink.Width * 2; dgv.Columns.AddRange(new DataGridViewColumn[] {ins,itemName,itemValue, mdfLink}); if (treeView1.SelectedNode.Tag != null) { ArrayList al = (ArrayList)treeView1.SelectedNode.Tag; foreach (object obj in al) { dgv.Rows.Add((DataGridViewRow)obj); } } else { // fill rows manually // ... } } private void treeView1_BeforeSelect(object sender, TreeViewCancelEventArgs e) { ArrayList al = new ArrayList(); foreach (DataGridViewRow dgvr in dgv.Rows) { al.Add(dgvr); } if (al.Count != 0) { treeView1.SelectedNode.Tag = al; } } And I need to store state of TreeView in a file by serialization to future restoring (I know that TreeView doesn't support serialization but TreeNoew does). But DataGridViewRow is not support serialization. As matter of fact I tried to store values in string arrays and populate it accordingly. My question is: 1. Is anybody know better way of serialization of treeview with attached DataGridView? 2. In case of using my method how do I save/restore selected item of ComboBoxCell? I will appreciate any help. Best regards, /Gelios Tag: Permit Single Instance of Form Tag: 98126
  - 10
    - Override of WebBrowserSite IDocHostUIHandler using WebBrowser.CreateWebBrowserSiteBase doesn't work According to http://msdn2.microsoft.com/en-us/library/system.windows.forms. webbrowser.createwebbrowsersitebase.aspx I should be able to customize the behavior of the System.Windows.Forms.WebBrowser control as follows: "To use this feature, implement classes that inherit from the WebBrowser and WebBrowser.WebBrowserSite classes. The unmanaged WebBrowser ActiveX control uses the protected CreateWebBrowserSiteBase method to retrieve extensibility interfaces implemented by the WebBrowser.WebBrowserSite class. Override the CreateWebBrowserSiteBase method to return an instance of your own class that inherits from the WebBrowser.WebBrowserSite class. The WebBrowser. WebBrowserSite class provides default implementations of the OLE IDocHostUIHandler. You can provide your own implementation of this interface or implement any other WebBrowser ActiveX control interface in order to customize the behavior of the control. If you provide your own implementation for any IDocHostUIHandler members, you must implement all the members of that interface." I've implemented my own classes and confirmed in debug that my version of CreateWebBrowserSiteBase is being called and creates my class. However, none of my IDocHostUIHandler methods are being called. I suspect that the problem may be in my constructor, which calls the WebBrowser.WebBrowserSite constructor, which creates a competing implementation of IDocHostUIHandler. The documentation implies that this should work. Am I missing anything? Any suggestions or workarounds? Thanks. Tag: Permit Single Instance of Form Tag: 98124
  - 11
    - Newbie - I am trying to integrate a native MFC dialog app into a Windows forms MDI Hi, I am quite a novice at programming in general, but have taken it upon myself to help my boss with a project of his. He developed an MFC dialog application (non-managed i believe) and wants me to incorporate it into a reporting tool I am developing with Crystal Reports. I am using MS Visual Studio 2005, which I found Crystal Reports to be highly integratable(sp?) with Windows Forms development, so that is what I have been using. Now the MFC dialog application i would like to integrate merely updates and queries a sql database, and I am trying to get it to load within an MDI i developed. What is the best way to accomplish this with preserving as much of the original code as possible? Any suggestions or helpful links would be greatly appreciative. Thanks:) Tag: Permit Single Instance of Form Tag: 98122
  - 12
    - DataGrid Sorting - Win forms .net 2003 Hi, I have a datagrid which is bound to a custom object's list item. I have to sort the datagrid. The moment I click on the header , the screen hangs. There are not too many records. About a 100. My list item implements a collection and is not a typical dataview. What should I do to sort it? Is it just enough to specify AllowSorting = true. What about Table Style. Any ideas ? PK Tag: Permit Single Instance of Form Tag: 98114
  - 13
    - No DataBinding unless explicit Validate() if AutoValidate.Disable If I have a Form on which I set AutoValidate to Disable and controls which are databound, then the contents of the controls won't be transferred to the data source unless Validate() or ValidateChildren() is called. Is this by design? Does anyone know of a work around? Thank you, Leif Wickland Tag: Permit Single Instance of Form Tag: 98113
  - 14
    - Detect button presses by intercepting WM_COMMAND I want to insert a 'general' message filter into a .NET application that will intercept button presses. IMessageFilter cannot be used because it only intercepts posted messages. So I override WndProc and filter on WM_COMMAND messages to detect button presses in the application. However the button presses are not being detected in my app. I have modified the app to have just one button on it and used spy++ to see what messages the button press generates. But nothing ! Any ideas ? Tag: Permit Single Instance of Form Tag: 98111
  - 15
    - Multiple Modeless forms, each with a Modal child form. I have the need for the following scenario: I creat 2 or more Modeless child forms from my main form. I can easily, as expected, switch betwenn them with no problem. Each modeless child form must be able to create a single Modal form. Due to the nature of the Modal form, I can't do this since once I've created the first Modal form as a child of one of the Modeless forms, I cannot switch focus to another of the Modeless forms inorder to create another Modal form. Briefly, here is the sequence of methods I want to use: MainForm: Call Dialog.Show() multiple times creating a new ChildForm each time. ChildForm: Call Dialog.ShowDialog() once (but I want to be able to do this in each ChildForm). Any ideas? Thanks in advance. Tag: Permit Single Instance of Form Tag: 98110
  - 16
    - Windows Form - Datagrid problem I have a dataset containing two related tables and a relation. I use the dataset's parent table as a datasource to a datagrid. This causes the diata to display with a '+' symbol at the left of the row - indicating the hierarchical relationship and allowing drilling into the child table. How can keep the same dataset but get rid of the '+' symbol in the datagrid? I am using C# and .Net version 1.1 Thanks Tag: Permit Single Instance of Form Tag: 98109
  - 17
    - Making "Everyone" the default option while installing the setup... I know the solution of setting the "Everyone" option by default at time of setup installation, by modifying the msi in the ORCA editor. Now, I have to create the msi with no dialog boxes(no start or progress interfaces), the problem is there's no way to change the default setting from 'Just Me' which is default to 'Everyone'. Can anyone suggest what could be the solution for this if it is alt all possible to do? Thanks for any suggestion and help. Tag: Permit Single Instance of Form Tag: 98104
  - 18
    - TableLayoutPanel - get cell clicked Hello, I had posted this to the C# group but then realised here might be more relevant. This seems like it should be simple - on the double-click event of a tablelayoutpanel, I want to know which cell was double clicked in. I can't see any of the properties that look relevant to this, could someone give me a pointer where to look? I can see various properties to give me the cell of a certain control and so on, but some cells might not have a control in yet (by double clicking the user will instigate the creation of a control in that cell - or at least that's the plan!) Thanks! James Tag: Permit Single Instance of Form Tag: 98102
  - 19
    - Hosting word on a form - supported My searches have not turned up anything, but is there a way to host winword on a form? It looks like the other office components are there, but word seems to be missing. Yes, I might use the browser control and navigate to a file but that seems fishy. I found some notes on SetParent and it being unreliable. Is there any official word? (Sorry for the bad pun.) The component that I am trying to interface (Dragon naturally speaking) likes word way more than it likes the richTextBox. (It has the habit of always inserting at position 2 in the rtb.) Thanks in advance Tag: Permit Single Instance of Form Tag: 98097
  - 20
    - Visual Studio 2005/.Net Framework 2.0 Certifications - Beta Offer Visual Studio 2005/.Net Framework 2.0 Certifications - http://www.microsoft.com/learning/mcp/newgen/ I am sending this post only to only related newgroups... Still my advanced appologies for cross posting, but have got a lots of feedback that folks did not get advance notification of beta exams as they never subscibed to a particular forum... Do note that only first 750 people will get an opportunity to take a particular Beta Exam and the offer will be on first come first serve basis... You can be a step closer to becoming "Microsoft Certified Professional Developer (MCPD)" with specialization in any of the below three tracks by taking a FREE Beta Exam. http://www.microsoft.com/learning/mcp/mcpd/default.asp MCPD Web Developer http://www.microsoft.com/learning/mcp/mcpd/webdev/ MCPD Windows Developer http://www.microsoft.com/learning/mcp/mcpd/windev/ MCPD Enterprise Application Developer http://www.microsoft.com/learning/mcp/mcpd/entapp/ And Also Win a Mobile Smartphone or a Wireless Keyboard!! Help us create great Microsoft Certification exams. Take the Beta version of Exams 70-547, 70-548, and/or 70-549 and you'll be automatically entered to win* one of two Windows Mobile Smartphones and one of 10 Microsoft Laser Desktop 6000 Keyboards. Only one entry per Beta exam, but if you take 2 different Betas you'll be entered 2 times, and if you take all 3 Betas you'll be entered 3 times. Microsoft employees and customers are eligible with a few restrictions - see below for all of the contest rules and regulations. Like the Beta Exams, this offer is not available in China, India, or Pakistan. And Also Earn a Free Exam Voucher In addition, everyone who takes and achieves passing score in the beta exam will receive a free exam voucher** for any Microsoft Certification Exam. Vouchers will be sent after exam scores are tabulated. This offer is also not available in China, India, or Pakistan. Exams Available Early Take the Betas starting February 21, 2006 at Pearson VUE locations, and starting February 27, 2006 at Thomson Prometric testing centers. Schedule your Beta exams today To register for this exam or for information about testing centers in your area, please visit the following Web sites for registration information: Thomson Prometric: http://securereg3.prometric.com/ Pearson VUE: http://www.vue.com/ms/ In the U.S./Canada you may also call to register for this exam or to find information about testing centers in your area: Thomson Prometric: (800) 755-EXAM (800-755-3926) Pearson VUE: 800 TEST Registration (800-837-8734) Use the following promotional codes to register: 71-547 PRO: Designing and Developing Web-based Applications by Using the Microsoft® .NET Framework. http://www.microsoft.com/learning/exams/70-547.asp Promo Code: PRO547 71-548 PRO: Designing and Developing Windows®-based Applications by Using the Microsoft® .NET Framework. http://www.microsoft.com/learning/exams/70-548.asp Promo Code: BTA548 71-549 PRO: Designing and Developing Enterprise Applications by Using the Microsoft® .NET Framework. http://www.microsoft.com/learning/exams/70-549.asp Promo Code: 549BTA * This sweepstakes invitation is for the Microsoft customers and employees, with some restrictions (see Official Rules below). Please forward to your colleagues, partners, and customers. ** Free exam voucher offer good only for people who pre-register for, and pass, Exams 71-547, 71-548, and 71-549. Limit one gift per person. This offer is non-transferable. This offer expires on March 12 2006, or when registration closes for this Beta exam. Beta exam registration has limited availability. This offer is not redeemable for cash. Taxes, if any, are the sole responsibility of the recipient. Any gift returned as non-deliverable will not be re-sent. wishes Vishal R Joshi Product Planner - Technical |Developer/Database Certifications, Microsoft. PS: For more information available at http://vishaljoshi.blogspot.com/2006/02/net-framework-20-certifications-beta.html PS: We are looking for more and more technical feedback on the exams so feel free to reach out to your user groups and communities and let developers know of this opportunity. Although do note that each exam caps at 750 Beta participants so there is an official upper limit. +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ The Microsoft Certification Beta Exam Sweepstakes Official Rules Please Note: It is your sole responsibility to review and understand your employer's policies regarding your eligibility to participate in trade promotions such as this one. If you are participating in violation of your employer's policies, you may be disqualified from entering this sweepstakes or receiving prizes. Microsoft disclaims any and all liability or responsibility for disputes arising between an employee and their employer related to this matter, and prizes will only be awarded in compliance with the employer's policies. 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This offer is void in the following regions: Cuba, Iran, Libya, North Korea, Sudan and Syria. This offer is not available in China, Pakistan and India. Employees of Microsoft, their affiliates, subsidiaries, and anyone working on this product, project, or promotion, and the advertising and promotional agencies and the immediate family members of each are not eligible. The sweepstakes opens at 12:01 AM PT on February 21, 2006 and ends at 11:59 PM PT on March 12, 2006. Void where prohibited by law. 2. How To Enter: No purchase Necessary. Enter by completing the free beta exams 71-547, 71-548, and 71-549 at a participating testing center and opt-in to enter this sweepstakes. To be eligible for the prize drawing, exams must be completed by 11:59 PM PT on March 12, 2006. A passing score is not required to receive a sweepstakes entry; however the beta exam must be completed in full to be eligible for the drawing. Limit one (1) entry per person per beta exam, for a total of 3 possible entries. Subsequent entries from the same individual will be automatically disqualified. No responsibility is assumed by Microsoft for lost, late, misdirected, illegible, postage due or mutilated entries or any computer, online telephone, or technical malfunctions that may occur. All entries become the property of Microsoft and will not be returned. 3. Winner Selection/Deadline Dates: On or around April 15, 2006, 12 winners will be chosen in a random drawing from among all eligible entries received to win one of the following prizes: Two winners: One (1) Windows Mobile Smartphone device. Estimated Retail Value US$500. Ten winners: One (1) Wireless Laser Desktop 6000 keyboard. Estimated Retail Value US$65. Actual retail value will vary based on the region where the winner resides, and any difference between estimated and actual value will not be awarded. Any prize won by a public sector employee will be awarded to their agency/institution in the form of Microsoft certification exam vouchers; the value not to exceed the estimated retail value of the alternate prizes. Random drawing will be conducted under the supervision of Microsoft, whose decisions are final. Odds of winning depend on the number of eligible entries received. All other expenses relating to the acceptance of the prize, which are not explicitly listed, are the responsibility of the winner. Prizes are not redeemable for cash. No substitution, transfer, or assignment of prize permitted, except that Sponsor reserves the right to substitute a prize of equal or greater value in the event an offered prize is unavailable. Taxes on the prizes are solely the responsibility of the winner. 5. General Conditions: Sweepstakes entrants agree to abide by the terms of these official rules and by the decisions of Microsoft which are final and binding on all matters pertaining to this Sweepstakes. This sweepstakes is governed by the laws of the State of Washington in the United States of America, and participants in the Sweepstakes hereby consent to the exclusive jurisdiction and venue of Washington courts (state and federal) for any causes or controversies arising out of the Sweepstakes. Winner will be notified within seven (7) days after the drawing date. Winner will be required to execute an affidavit of eligibility and liability/publicity release within seven (7) days following the date of attempted notification. Non compliance within this time period may result in disqualification and selection of an alternate winner. Return of any prize/ prize notification as undeliverable may result in disqualification and selection of an alternate winner. Entrants further grant to Microsoft the right to use and publish their proper name and state online and in print in any other media in connection with the Sweepstakes. Acceptance of a prize constitutes permission for Microsoft to use winner's names and likenesses for advertising and promotional purposes without additional compensation unless prohibited by law. By entering, participants release and hold harmless Microsoft, their respective parents, subsidiaries, affiliates, directors, officers, employees and agents from any and all liability or any injuries, loss or damage of any kind arising from or in connection with this Sweepstakes or any prize won. 6. Winners List: The names of the winners will be available after April 15, 2006, by sending email to mcphelp@microsoft.com. 8. Sponsor: This Sweepstakes is sponsored by Microsoft Corporation, One Microsoft Way, Redmond, WA 98052. This post is provided "AS IS" with no warranties, and confer no rights. Tag: Permit Single Instance of Form Tag: 98095
  - 21
    - Solution / Request for Suggestions: DataGrid Button Column using C# I've tried to find examples of adding a button column to a WinForms DataGrid. Unfortunately, all of the examples I have found only allow you to click on the button for the currently selected row. Below is a class that I wrote that displays clickable buttons for each row along with a sample form that uses the class. Hopefully this will help some people out. If you try this code, please post some feedback on suggestions for improvements or bugs. This has been in use in a few applications for a couple months and seems to be stable and reliable. However, I'm still a little concerned about the mouse event handlers that are registered with the underlying DataGrid. Thanks! To use this example, create a new Windows Forms project, add a new class module to the project, and then do the following. 1. Paste this code into the class module: using System; using System.Windows.Forms; using System.Drawing; using System.Drawing.Drawing2D; using System.Diagnostics; namespace TestApp { /// <summary> /// Adds a column to a DataGrid that displays /// a button that can be responded to /// via an event that fires when it is clicked. /// </summary> /// <remarks> /// Major gotcha: adding this DataGridColumnStyle /// to a DataGrid will register /// handlers with the MouseDown, MouseUp, and /// MouseMove events in the DataGrid. /// Therefore, destroying a DataGrid's TableStyle and /// adding a new one will cause /// unexpected behavior if the mouse handlers are not /// removed manually before hand. /// </remarks> public class DataGridButtonColumn : DataGridColumnStyle { /* * Fires when a button is clicked in this column. */ public delegate void ClickEventHandler(object sender, DataGridButtonEventArgs e); public event ClickEventHandler Click; private int _xMargin = 2; private int _yMargin = 1; private string _buttonName = ""; private bool _editing = false; private int _editingRowNum = 0; private bool _isMouseDown = false; private int _mouseRow = -1; private int _mouseCol = -1; private DataGrid.HitTestInfo _mousePos = null; public DataGridButtonColumn(string buttonName) { _buttonName = buttonName; } #region Overridden methods protected override void Abort(int rowNum) { Debug.WriteLine("Abort()"); endEdit(); } protected override bool Commit(CurrencyManager dataSource, int rowNum) { if(_editing) { endEdit(); } return true; } protected override void Edit(CurrencyManager source, int rowNum, Rectangle bounds, bool readOnly, string instantText, bool cellIsVisible) { _editingRowNum = rowNum; _editing = true; } protected override void Paint(Graphics g, Rectangle bounds, CurrencyManager source, int rowNum) { /* * Propogate to the next Paint() handler. */ Paint(g, bounds, source, rowNum, false); } protected override void Paint(Graphics g, Rectangle bounds, CurrencyManager source, int rowNum, bool alignToRight) { /* * Create a buffer to draw to. (Double-buffering) */ Bitmap buffer = new Bitmap(bounds.Width, bounds.Height); Graphics bg = Graphics.FromImage(buffer); Rectangle bufferBounds = new Rectangle(0, 0, bounds.Width, bounds.Height); /* * Default background for the cell. */ Brush backBrush; if(rowNum % 2 == 0) { backBrush = new SolidBrush(this.DataGridTableStyle.BackColor); } else { backBrush = new SolidBrush(this.DataGridTableStyle.AlternatingBackColor); } Brush foreBrush = new SolidBrush(this.DataGridTableStyle.ForeColor); bg.FillRectangle(backBrush, bufferBounds); /* * Draw the button. */ Rectangle buttonBounds = bufferBounds; buttonBounds.Offset(_xMargin, _yMargin); buttonBounds.Width -= _xMargin * 2; buttonBounds.Height -= _yMargin * 2; /* * The "Down" state requires that the button on this row has had the mouse * down event fired on it and the mouse must still be over top of this button. */ if(_isMouseDown && rowNum == _mouseRow && _mousePos != null && _mousePos.Row == _mouseRow && _mousePos.Column == _mouseCol) { DrawDown(bg, buttonBounds); bounds.Offset(1, 1); PaintText(bg, bufferBounds, _buttonName, foreBrush, alignToRight); } else { DrawUp(bg, buttonBounds); PaintText(bg, bufferBounds, _buttonName, foreBrush, alignToRight); } /* * Render the secondary buffer to the real buffer. */ g.DrawImageUnscaled(buffer, bounds); } protected override void Paint(Graphics g, Rectangle bounds, CurrencyManager source, int rowNum, Brush backBrush, Brush foreBrush, bool alignToRight) { /* * Let the base class handle any painting needs. */ base.Paint(g, bounds, source, rowNum, backBrush, foreBrush, alignToRight); } protected override int GetMinimumHeight() { return 0; } protected override int GetPreferredHeight(Graphics g, object value) { return 0; } protected override Size GetPreferredSize(Graphics g, object value) { return new Size (0, 0); } protected override void SetDataGridInColumn(DataGrid value) { base.SetDataGridInColumn (value); /* * Add the mouse handlers, but make certain that there is only * one handler registered per event. */ RemoveMouseHandlers(value); AddMouseHandlers(value); } #endregion #region Helper functions public void RemoveMouseHandlers(DataGrid dg) { dg.MouseDown -= new MouseEventHandler(DataGridMouseDown); dg.MouseUp -= new MouseEventHandler(DataGridMouseUp); dg.MouseMove -= new MouseEventHandler(DataGridMouseMove); } private void AddMouseHandlers(DataGrid dg) { dg.MouseDown += new MouseEventHandler(DataGridMouseDown); dg.MouseUp += new MouseEventHandler(DataGridMouseUp); dg.MouseMove += new MouseEventHandler(DataGridMouseMove); } private void endEdit() { _editing = false; Invalidate(); } private void PaintText(Graphics g, Rectangle TextBounds, string Text, Brush ForeBrush, bool AlignToRight) { Rectangle Rect = TextBounds; RectangleF RectF = Rect; StringFormat Format = new StringFormat(); if(AlignToRight) { Format.FormatFlags = StringFormatFlags.DirectionRightToLeft; } switch(this.Alignment) { case HorizontalAlignment.Left: Format.Alignment = StringAlignment.Near; break; case HorizontalAlignment.Right: Format.Alignment = StringAlignment.Far; break; case HorizontalAlignment.Center: Format.Alignment = StringAlignment.Center; break; } Format.FormatFlags = Format.FormatFlags; Format.FormatFlags = StringFormatFlags.NoWrap; Rect.Offset(0, _yMargin); Rect.Height -= _yMargin; g.DrawString(Text, this.DataGridTableStyle.DataGrid.Font, ForeBrush, RectF, Format); Format.Dispose(); } private void DrawUp(Graphics g, Rectangle bounds) { // Face g.FillRectangle(new SolidBrush(SystemColors.ControlLight), bounds); // Light edges Point[] pt = new Point[3]; pt[0] = new Point(bounds.Left, bounds.Bottom); pt[1] = new Point(bounds.Left, bounds.Top); pt[2] = new Point(bounds.Right, bounds.Top); g.DrawLines(Pens.White, pt); // Dark-dark shadow pt[0] = new Point(bounds.Right, bounds.Top); pt[1] = new Point(bounds.Right, bounds.Bottom); pt[2] = new Point(bounds.Left, bounds.Bottom); g.DrawLines(new Pen(SystemColors.ControlDarkDark), pt); // Dark shadow pt[0] = new Point(bounds.Right-1, bounds.Top+1); pt[1] = new Point(bounds.Right-1, bounds.Bottom-1); pt[2] = new Point(bounds.Left+1, bounds.Bottom-1); g.DrawLines(new Pen(SystemColors.ControlDark), pt); } private void DrawDown(Graphics g, Rectangle bounds) { // Face g.FillRectangle(new SolidBrush(SystemColors.ControlLight), bounds); // Light edges Point[] pt = new Point[3]; pt[0] = new Point(bounds.Left, bounds.Bottom); pt[1] = new Point(bounds.Left, bounds.Top); pt[2] = new Point(bounds.Right, bounds.Top); g.DrawLines(Pens.White, pt); // Light-light edges pt[0] = new Point(bounds.Left+1, bounds.Bottom-1); pt[1] = new Point(bounds.Left+1, bounds.Top+1); pt[2] = new Point(bounds.Right-1, bounds.Top+1); g.DrawLines(new Pen(SystemColors.ControlLightLight), pt); // Dark shadow pt[0] = new Point(bounds.Right, bounds.Top); pt[1] = new Point(bounds.Right, bounds.Bottom); pt[2] = new Point(bounds.Left, bounds.Bottom); g.DrawLines(new Pen(SystemColors.ControlDark), pt); } private int getColumnNumber() { /* * For some reason, there is no way to determine what column you occupy * without traversing the entire column collection and finding yourself. */ for(int i = 0; i < this.DataGridTableStyle.GridColumnStyles.Count; i++) { if(this == this.DataGridTableStyle.GridColumnStyles[i]) { return i; } } return -1; } #endregion #region Event handlers private void DataGridMouseDown(object sender, MouseEventArgs e) { /* * Ignore all clicks other than left clicks. */ if(e.Button != MouseButtons.Left) { return; } /* * Store the row / column pair that this mouse down event occurred on. */ DataGrid dg = this.DataGridTableStyle.DataGrid; DataGrid.HitTestInfo ht = dg.HitTest(new Point(e.X, e.Y)); _mouseRow = ht.Row; _mouseCol = ht.Column; Debug.WriteLine("Down: " + ht); /* * Only set the _isMouseDown state to true if this column was clicked. */ if(_mouseCol == getColumnNumber()) { _isMouseDown = true; _mousePos = ht; } Invalidate(); } private void DataGridMouseUp(object sender, MouseEventArgs e) { /* * Store the row / column pair that this mouse up event occurred on. * Later, the Paint() event will test to see if it was a valid click on * a button and fire the ButtonClicked event if it was a valid click. */ DataGrid dg = this.DataGridTableStyle.DataGrid; DataGrid.HitTestInfo ht = dg.HitTest(new Point(e.X, e.Y)); Debug.WriteLine("Up: " + ht); if(_isMouseDown && ht.Row == _mouseRow && ht.Column == _mouseCol) { Debug.WriteLine("Clicked " + ht); // Fire the Click event if someone has registered to receive it if(Click != null) { Click(this, new DataGridButtonEventArgs(_mouseRow, _mouseCol)); } } _isMouseDown = false; _mousePos = null; Invalidate(); } private void DataGridMouseMove(object sender, MouseEventArgs e) { /* * Determine if the button needs switch state to an up or down position. * * We want to emulate the behavior of a button springing up if the mouse * was clicked down on it and then moved off before the mouse button is * released. We also need the button to push itself back down if the * mouse moves back over the button. */ if(_isMouseDown) { DataGrid dg = this.DataGridTableStyle.DataGrid; DataGrid.HitTestInfo ht = dg.HitTest(new Point(e.X, e.Y)); if(ht != _mousePos) { _mousePos = ht; Invalidate(); } } } #endregion } /// <summary> /// EventArgs class that includes the row and column that was clicked. /// </summary> public class DataGridButtonEventArgs : EventArgs { private int _column; private int _row; public DataGridButtonEventArgs(int row, int col) { _row = row; _column = col; } public int Column { get { return _column; } } public int Row { get { return _row; } } } } 2. Overwrite the code in Form1.cs with this code: using System; using System.Drawing; using System.Collections; using System.ComponentModel; using System.Windows.Forms; using System.Data; namespace TestApp { public class Form1 : System.Windows.Forms.Form { private System.Windows.Forms.DataGrid dgTest; private System.ComponentModel.Container components = null; public Form1() { InitializeComponent(); /* * Create dummy data. This should be pulled from a database in reality. */ DataTable dt = new DataTable("ButtonSample"); dt.Columns.Add("Sample1"); dt.Columns.Add("Sample2"); dt.Columns.Add("Unbound1"); /* Necessary for the button column to bind to. Can this be avoided? */ for(int i = 0; i < 10; i++) { DataRow row = dt.NewRow(); row["Sample1"] = i.ToString(); row["Sample2"] = (i * 2).ToString(); dt.Rows.Add(row); } dgTest.DataSource = dt; /* * Create a DataGridTableStyle with a button column. */ DataGridTableStyle dgts = new DataGridTableStyle(); dgts.MappingName = dt.TableName; dgts.GridColumnStyles.Add( CreateTextBoxColumn("Sample1", "Sample 1")); dgts.GridColumnStyles.Add( CreateTextBoxColumn("Sample2", "Sample 2")); DataGridButtonColumn buttonCol = new DataGridButtonColumn("Test"); buttonCol.MappingName = "Unbound1"; buttonCol.HeaderText = "Button"; buttonCol.Click += new TestApp.DataGridButtonColumn.ClickEventHandler(buttonCol_Click); dgts.GridColumnStyles.Add(buttonCol); dgTest.TableStyles.Add(dgts); } private DataGridTextBoxColumn CreateTextBoxColumn(string mappingName, string headerText) { DataGridTextBoxColumn col = new DataGridTextBoxColumn(); col.MappingName = mappingName; col.HeaderText = headerText; col.NullText = ""; return col; } protected override void Dispose( bool disposing ) { if( disposing ) { if (components != null) { components.Dispose(); } } base.Dispose( disposing ); } #region Windows Form Designer generated code /// <summary> /// Required method for Designer support - do not modify /// the contents of this method with the code editor. /// </summary> private void InitializeComponent() { this.dgTest = new System.Windows.Forms.DataGrid(); ((System.ComponentModel.ISupportInitialize)(this.dgTest)).BeginInit(); this.SuspendLayout(); // // dgTest // this.dgTest.DataMember = ""; this.dgTest.HeaderForeColor = System.Drawing.SystemColors.ControlText; this.dgTest.Location = new System.Drawing.Point(8, 8); this.dgTest.Name = "dgTest"; this.dgTest.Size = new System.Drawing.Size(456, 288); this.dgTest.TabIndex = 0; // // Form1 // this.AutoScaleBaseSize = new System.Drawing.Size(5, 13); this.ClientSize = new System.Drawing.Size(472, 302); this.Controls.Add(this.dgTest); this.Name = "Form1"; this.Text = "Form1"; ((System.ComponentModel.ISupportInitialize)(this.dgTest)).EndInit(); this.ResumeLayout(false); } #endregion [STAThread] static void Main() { Application.Run(new Form1()); } private void buttonCol_Click(object sender, DataGridButtonEventArgs e) { DataGrid x = ((DataGridButtonColumn)sender).DataGridTableStyle.DataGrid; CurrencyManager cm = (CurrencyManager)BindingContext[x.DataSource]; DataRow r = ((DataRowView)cm.List[e.Row]).Row; MessageBox.Show( "Sample 1: " + r["Sample1"].ToString() + ", Sample 2: " + r["Sample2"].ToString()); } } } Tag: Permit Single Instance of Form Tag: 98083
  - 22
    - Playing an animated gif file in a windows form application. What's the easiest way to play an animated gif in a windows forms application? TIA - Jeff. Tag: Permit Single Instance of Form Tag: 98081
  - 23
    - How to make DataDridViewComboBoxColumn editable I am using VS 2005. The DataDridViewComboBoxColumn in the datadridview is not letting me edit (type in) the text in combobox. All i could do is select an option from the list. Any idea how to make DataDridViewComboBoxColumn editable? Thanks in advance. Tag: Permit Single Instance of Form Tag: 98079
  - 24
    - ListView SelectedIndexChanged Firing Twice, possible solution? I know that by design, the SelectedIndexChanged event fires twice when the SelectedIndex changes, once for the unselection of the previous index, and once for the selection of the new index. This is somewhat bothersome to me because I have listeners for those events that toggle the enabled states of other controls on the form based on whether an item is selected or not, and this creates an ugly blinking effect. Is there any way to peek into the message queue and see if there is another SelectedIndexChange event coming? I know I can't see into the future, but I'm hoping the messages will be placed into the queue simultaniously and that they will both be in the queue when I recieve the first event. My current solution, which I'm not really that pleased with, is to have a Timer t on the form with a 100 millisecond interval. When the SelectedIndexChanged event fires, I check a flag to see if the timer is running. If it's not running, I start the timer and set the flag. On the Tick event of the timer, I fire my own SelectedItemChanged event, stop the timer, and reset the flag. Basically what's happening is I'm only allowing one SelectedIndex event to fire within any given 100 millisecond window. This works, I don't get the flickering, but it seems kinda hackish and unpredicable. Any better suggestions? Tag: Permit Single Instance of Form Tag: 98076
  - 25
    - Width of textbox on a FlowLayoutPanel Hi, I have three textboxes on the same row on a FlowLayoutPanel. I want the one on the left and right to have a fixed width but for the one in the middle to fill any remaining space depending on the width of the FlowLayoutPanel. Is this possible? (The widths of the left and right boxes aren't known until runtime). I was thinking that I could handle the SizeChangingEvent and work out the width to set the middle text box to. This would basically be: width of FlowLayoutPanel - width of left text box- width of right text box. However, I don't know how to determine what controls are on the same row in order to retrieve their width?! Any help appreciated. Thanks Tristan. Tag: Permit Single Instance of Form Tag: 98074

What is a generally accepted method used to ensure that one instance, at
most, of a form can be opened?

Thanks

Re: Permit Single Instance of Form by Bob

Bob
Tue Feb 28 06:24:06 CST 2006

An instance of a form or an application?

For the application, see the article in Windows Forms Tips and Tricks.

For a form, you could create the form as a singleton but remember to use
show and hide to display or remove the form.

--
Bob Powell [MVP]
Visual C#, System.Drawing

Ramuseco Limited .NET consulting
http://www.ramuseco.com

Find great Windows Forms articles in Windows Forms Tips and Tricks
http://www.bobpowell.net/tipstricks.htm

Answer those GDI+ questions with the GDI+ FAQ
http://www.bobpowell.net/faqmain.htm

All new articles provide code in C# and VB.NET.
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"Jeff S" <A@B.COM> wrote in message
news:%23pqFDODPGHA.3936@TK2MSFTNGP12.phx.gbl...
> What is a generally accepted method used to ensure that one instance, at
> most, of a form can be opened?
>
> Thanks
>

Top

Re: Permit Single Instance of Form by Nick

Nick
Tue Feb 28 07:08:55 CST 2006

"Jeff S" <A@B.COM> wrote in message
news:%23pqFDODPGHA.3936@TK2MSFTNGP12.phx.gbl...
> What is a generally accepted method used to ensure that one instance, at
> most, of a form can be opened?

There isn't one because it is difficult to think of any reason why you would
want to do that.

The more usual case is that you want to create the form if it doesn't exist
OR bring an existing one to the front.

Typically I would use a private property on whatever it is that normally
controls the form so that it creates the form on demand so that something
like obj.MyForm.Show() would always work.

It might be that you have a genuine need for the form itself to be a
singleton but I have never come across a case where it was necessary.

Top

Re: Permit Single Instance of Form by Cerebrus

Cerebrus
Tue Feb 28 11:32:17 CST 2006

Check out this link:

http://www.codeproject.com/vb/net/Simple_Singleton_Forms.asp

It might prove useful.

Regards,

Cerebrus.

"Jeff S" <A@B.COM> wrote in message
news:#pqFDODPGHA.3936@TK2MSFTNGP12.phx.gbl...
> What is a generally accepted method used to ensure that one instance, at
> most, of a form can be opened?
>
> Thanks
>
>

Top