Control Addition safety handling

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  - 1
    - Label with Transparent Background I need to have text displayed over a picturebox with an image in it. When using a label whose BackColor = System.Drawing.Color.Transparent, the background is not transparent. I came across this explanation as to why .Net does not support transparent backgrounds. ************ [In Visual Basic 6.0, the BackStyle property of the Label control determined whether the label had a transparent background. Setting the BackStyle property to 0 â?? Transparent allowed any background image or other controls to show through the label. In Visual Basic .NET, the BackStyle property no longer exists, and the transparency behavior is slightly different. To emulate the transparent behavior in Visual Basic .NET, set the BackColor property to System.Drawing.Color.Transparent. This will allow the background image to show through, but it will not be transparent in regard to other controls.] ********************** The last phrase is mindboggling, " . . . but it will not be transparent in regards to other controls." What good it is then??? Why would any lanquage designer not support such a useful property? How do I get a label to have a true transparent background?? WR -- William R Tag: Control Addition safety handling Tag: 82236
  - 2
    - Inheritance in forms which inherit template forms I have this "template" form which is based on System.Windows.Forms.Form. I created a new form(the derived form) which inherits this form. I have observed that if, at runtime, I run through all of the controls in the controls collection of the "template" form, I can have access to all the controls that exist in the derived form! Now this seems odd to me; why should a base class have the controls of a class above it (the derived form), in its controls collection. Certainly I would expect the class derived from the template to see all the controls on the base class but not the other way around. -- Michael Hockstein Tag: Control Addition safety handling Tag: 82235
  - 3
    - printing code without windows generated How can I print the code for a form without including the windows form designer generated code? thanks. dennist685 Tag: Control Addition safety handling Tag: 82233
  - 4
    - Problem with FileSystemWatcher/Tray Notifier App Hi, I've been developing an application in VB.NET that uses the FileSystemWatcher and a popup notification in order to tell me when files have been downloaded. The FileSystemWatcher code in my project is basically the same one thats floating all over the VB.NET sites (by Jayesh Jain). The popup notification (called TaskbarNotifier) is a class originally by John O'Byrne written in C# and C++ but ported to VB.NET by Patrick Vanden Driessche. It was downloaded from codeproject.com. Both of these elements (FileSystemWatcher and TaskBarNotifier) work perfectly on the own but I experienced problems when I tried incorporating and combining them in my own project. Basically, the FileSystemWatcher will detect files created, changed, deleted etc and the TaskBarNotifier will display popups as it should. The problem comes when I create a file (by means of downloading it or by just copying it to the 'watched' folder directly). I've coded it so the TaskBarNotifier should popup with name of the file created/downloaded then disappear after 3 seconds. It should, but doesn't. I can't understand why the same code will not run when used under a different procedure. I would of prefered to paste the code here in the hope people willing and able to help can paste it directly into their own VB.NET environment but the project contains bitmaps (as Embedded Resources) for the skins of the popups and they need to be included when compiling/testing the app otherwise it won't compile. So for this reason I've posted the project on my website for download. Homepage: http://www.geocities.com/toffee_paul/fun_d_mental.html Direct Link: http://www.geocities.com/toffee_paul/vbnetproj.zip When compiled and the form is displayed, click 'Test just the Popup' and the popup will appear as it should. Now change the 'watch folder' to a valid folder and copy a file to this folder. The app will detect the newly created file (as proven in the 'content' textbox) but the popup will fail to appear. Very strange problem. Any help is very much appreciated, Thanks Paul Tag: Control Addition safety handling Tag: 82232
  - 5
    - Webbrowser Hide Bug (Solution) I don't think anybody has ever come up with a satisfactory solution to the bug where the webbrowser control, hosted in an MDI child, breaks when the form is hidden and reshown. I think this problem also sometimes manifests itself in non-MDI forms too. The solution I came up with was very simple and seems to work perfectly. State is maintained perfectly and you don't have to reload the page or anything. 1) Wrap the webbrowser control in your own UserControl (I recommend the WebOCHostVB... search for it in MS KB... Article ID 311303). 2) In the usercontrol's HandleDestroyed event remove the webbrowser from the Controls collection (and add it back in the HandleCreated event). This prevents the orphaning of the webbrowser window. Private Sub WebOCHostCtrl_HandleDestroyed(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.HandleDestroyed 'detach the browser If Not webBrowser Is Nothing Then If Me.Controls.Contains(webBrowser) Then Me.Controls.Remove(webBrowser) End If End If End Sub Private Sub WebOCHostCtrl_HandleCreated(ByVal sender As Object, ByVal e As System.EventArgs) Handles MyBase.HandleCreated 'attach the browser If Not webBrowser Is Nothing Then If Not Me.Controls.Contains(webBrowser) Then Me.Controls.Add(webBrowser) webBrowser.Width = Me.ClientRectangle.Width webBrowser.Height = Me.ClientRectangle.Height End If End If End Sub That's it! Tag: Control Addition safety handling Tag: 82231
  - 6
    - Resource Files, Satellite Assembly - newbie This has been bothering me for the last couple of hours. Here is what I would like to do. I want to create a sample when a button is clicked, depending on Culture I would like to display the flag. What I did was create a resx file using ResxResourceWriter and AddResource Method. I included few countries' flags in the resx file. I used resgen to create the .resource file. I am using the following lines of code: rm = New ResourceManager("MyImages", Me.GetType().Assembly) and PictureBox1.Image = CType(rm.GetObject("MyImage", ci), System.Drawing.Image) Using the reseditor I could see the bitmap files in the file. When I run the sample I keep getting the error - ********************************************** An unhandled exception of type 'System.Resources.MissingManifestResourceException' occurred in mscorlib.dll Additional information: Could not find any resources appropriate for the specified culture (or the neutral culture) in the given assembly. Make sure "MyImages.resources" was correctly embedded or linked into assembly "ResourceFileSample". I tried including the .resources file in the peoject, compiled but still got the same error. I tried creating the resource dll and included in the reference but no change. I have the subdirectories created for the test Cultures an d created the corresponding resource files. Is my understanding wrong? Please help or any links that I can look into will be a great help Tag: Control Addition safety handling Tag: 82227
  - 7
    - textbox data entry I enter data into several textbox's. and try to save it to a SQL table using the following code: Before this code is executed I do a 'sqlDataAdapter->Clear', and then enter the new data. private: System::Void btnOSave_Click(System::Object * sender, System::EventArgs * e) { void UpdateDataSet(DataSet* dsOwnerAnimal1); // Check for changes to the dataset if(!dsOwnerAnimal1->HasChanges(DataRowState::Modified)) return; MessageBox::Show("we got here 2"); // Create a temporary Dataset DataSet* xOwner; MessageBox::Show("we got here 3"); // Get the changes to the data (Modified Rows Only) xOwner = dsOwnerAnimal1->GetChanges(DataRowState::Modified); MessageBox::Show("we got here 4"); // Check the Dataset for Errors if(xOwner->HasErrors) { MessageBox::Show("There were Errors, Did not Update!"); return; } This does not work because I get no data into the dsOwnerAnimal1 dataset. Can someone tell me what I am doing wrong? Norm -- Message posted via http://www.dotnetmonster.com Tag: Control Addition safety handling Tag: 82220
  - 8
    - Check multiple radion buttons in panel I have a vb.net 1.1 winforms app and have several radio buttons in a panel control. I want to be able to check several of the buttons at the same time, but their behavior is that when I check one the other button becomes unchecked so its not possible to have 2 checked at the same time. Is there a way to work around this? Thanks. -- moondaddy@nospam.com Tag: Control Addition safety handling Tag: 82217
  - 9
    - Detect when owned form is brought to front? Sorry about the last post -- I hit Enter by accident... I have the following code ('this' is a non-MDI Form): Form form1 = new Form(); form1.Owner = this; form1.Show() Form form2 = new Form(); form2.Owner = this; form2.Show(); The behavior is that form1 and form2 are sort of child forms of 'this' form. When the above code is executed, form2 is in the front, and I'd like to check when the user clicks on form1 to bring it to the front. I guess I was assuming that this was the 'GotFocus' event but this does not work. Is there a 'ZOrderChange' event, or what is it? Thanks. Tag: Control Addition safety handling Tag: 82213
  - 10
    - Visual C# Unable to alter size or position of form Hi I have this in a method which is called when my form is created public CreateDevice() { // Set the initial size of our form this.Top = 0; this.Left = 0; this.Size = new System.Drawing.Size(500,800); //this.ClientSize = new System.Drawing.Size(400,300); // And it's caption this.Text = "Rhubarb: CreateDevice"; // Load our icon from the resources of the .exe this.Icon = new Icon(this.GetType(), "directx.ico"); } the method is being called OK, because the forms text is being set to what ever I want it to be. But attempts to set the Top, Left or Size members are having no effect at all, the same with attempts to set the ClientSize member. I can resize the form by dragging, when it is running. I am completely new to C# so it may be something really dumb. Any ideas Kevin R. Tag: Control Addition safety handling Tag: 82208
  - 11
    - Determine CAPS LOCK state in VB. NET Is there any way to determine the CAPS LOCK state in VB. NET, without calling any VB6-style Windows API? Tag: Control Addition safety handling Tag: 82206
  - 12
    - How can I profile or check the performance of winforms hosted by IE? Hi, I'm working with "Smart Client" technology ... meaning I'm developing Winforms application embedded in IE. In my form, there are a bunch of controls and objects that connects to SQL DB Severs and to WebServices just like other rich client application. Smart client development process was really tough but had to ran through it. Since now debugging process is on its edge, I'm planning to optimize my Winforms application (embedded in IE). So...I wonder is there anyway to check the performance of "Smart Client". I just want to optimize my app's code to enhance performance. Especially I want to check the memory usage, cpu usage, time consumed, object created based on each line of code execution. Is this possible? Please consider this is unusual situation(winforms in IE). Any suggestion would be appreciated. TIA. :) Regards, Ryan Tag: Control Addition safety handling Tag: 82204
  - 13
    - mdi client problems - second try In our app (VB) client forms are displayed based on what is on the current client form and the button pressed. A user never selects a client form. You can think of this process as filling out a very long form with many branches (e.g., IRS form 1040). Once a client form is loaded it is never unloaded - just hidden. I need help resolving these 2 problems: 1) Focus on a text box. I know i can't set the focus in the Load event but the Activated event only fires when the first client loads. Also, when the form is redisplayed (i.e., made visible) txtbox.focus, for example, doesn't work. What I do now is start a timer with a 10ms interval and set the focus in the timer event. I also think that sometimes when I leave the text box the Leave event doesn't always fire. There's got to be a better way. 2) Client form size. I would like the client form to be the maximum size that will fit in the MDI parent. The minimum size of the client forms is set to 720 X 540. If i set the WindowState to Maximized the first client is displayed maximized but all the others are displayed at their minimum size. When the first client form is redisplayed it is also displayed at the minimum size. This just drives the users crazy. What I've done is after showing the form the first time or making the form visible on redisplays I set the child.Dock = DockStyle.Fill. I also do this if the parent is resized. Now the client is almost maximum size except it still has its own margins. -- tsiGeorge Tag: Control Addition safety handling Tag: 82203
  - 14
    - About smart client authentication Suppose I want to implement a single windows form as a smart client for scanning and editing, uploading images to webserver...since this is going to be a web deployed windows form...and basically i will have a link on the web form for this windows form to be loaded(web application uses webform authentication by backend database)..now when the user clicks the link for the windows form i need to check that the user is authenticated...is there a way where i can integrate my webapplication's authentication into this windows form..is there a way to access session variables within the windows form and/or cookies...is there a way to inherit asp.net multi threading feature into this form??...or do i have to implement multithreading myself??if so how do i do that??...i am clueless about windows applications. I just want to know how people are autheticating users in smart client Any help will be greatly appreciated. TIA. :) Tag: Control Addition safety handling Tag: 82199
  - 15
    - Problems Positioning Toolbars Hi I am self learning .VB .Net and have encountered a requirement that is not illustrated in any of my texts. I have three toolbars which can be present in any combination from 0-3 They are quite small and when there are two or three I would like the first pair to lie alongside each other I have been fiddling for ages with code to do this. The latest version is listed below. It always leaves three toolbars full width stacked vertically. I would be grateful for some advice on how to achieve this. Yours with thanks in anticipation Roger Stenson 'Current Code If (CurrentUser.UserStatus = "Authenticated") And (CurrentUser.UserLevel = "Administrator") Then 'Basic Toolbar tbrBasic.Visible = True tbrBasic.Enabled = True tbrBasic.Size = New Size(233, 16) tbrBasic.Location = New Point(0, 0) 'User Toolbar tbrUser.Visible = True tbrUser.Enabled = True tbrBasic.Size = New Size(233, 16) tbrUser.Location = New Point(224, 0) 'Administrator Toolbar tbrAdministrator.Visible = True tbrAdministrator.Enabled = True tbrBasic.Size = New Size(233, 16) tbrUser.Location = New Point(0, 17) Tag: Control Addition safety handling Tag: 82198
  - 16
    - AfterCheck event for TreeView control Hi, I registered event handler to catch the AfterCheck event... myTreeView.AfterCheck += new TreeViewEventHandler(myTreeView_....); It works fine, however, if I set the checkbox as true or false programatically(I mean..in the code, somethinglike node.Checked = true...), aftercheck event wasn't fired. Of course, if I checked the checkbox by mouse or keyboard, the event was fired. However, again, programatically set checkbox didn't invoke the aftercheck event. Am I missing something? Any suggesion would be appreciated. Thanks. ...............................................TJ Tag: Control Addition safety handling Tag: 82197
  - 17
    - Wrong Application Icon Task Switch I have a C# application with one and only one icon in the project. The icon is linked as the application icon in Project Properties and is also linked with each windows form. The icon is displayed properly on the desktop, in the task bar, and on the form itself. However, when you task switch (Alt+Tab) the icon is replaced with a generic icon. Why? How do I get the proper icon to show on the task switch dialog? --Kevin Tag: Control Addition safety handling Tag: 82196
  - 18
    - After form loads event Hi This question is probably one of the basic things but being a novice programmer in c# and .NET environment, I couldn't get to find the answer. I have a menu item in one form and need to create the context menu with tht menu item in another form. The first form becomes the parent form for the second form after the second form is loaded. So, I need to know what event could be used as load event is called when the form is still in the process of loading. Thanks Tag: Control Addition safety handling Tag: 82194
  - 19
    - changing look and feel of an app I would like to know if there are any examples, tutorial on how to completely change an application's look and feel. By that I mean the colors, the way menus are drawn, the way tool bar items are spaced in a tool bar, the way tab identifiers are shaped, etc., etc. There are a few interesting 'LAFs' such as MS Money 2005, MSN Messenger 6.2, Office 2003...just to name a few basic ones. I would like to have one of my graphic designer friends do a mock up in photoshop then produce an application that looks like it (I'm assuming it all has to be done programatically so designers would have to resort to something like photoshop). I also understand that part of the reason the aforementioned applications look the way they do is because of controls which are not available publicly...despite that, if designer can create websites (with primitive components) that can draw powerful and diverse emotional reactions, I don't understand why rich client GUIs have to look so ugly and gray (obviously 'consistency' has its place too). Any way, it will be even better if someone can point me to publicly available LAFs, the way we are starting to see them for the Java/SWING community. Thanks! Tag: Control Addition safety handling Tag: 82190
  - 20
    - Overriding OnPaint with a ListView Hi all, here is what I want to do: I've got a ListView populated from a database. The problem is that there is two much items generated... So I wanted to only get additionnal data (all the colums) for the painted items. To do so I created my own ListView class derivated from the original one and I've overriden the OnPaint method. BUT this function's never called............ Somebody knows why? Or even more, sombedy would have another solution to solve my problem? Thanks in advance!!! Tag: Control Addition safety handling Tag: 82189
  - 21
    - Use Outlook 2003 buttons, etc. How can I develop a windows application that uses controls in Office 2003, especially Outlook. Jay Tag: Control Addition safety handling Tag: 82186
  - 22
    - View of ListControl Item I have a ListControl on a window where the text will get clipped. The user can not see the full text nor can he scroll to view it. Questions: 1) Is there a Windows "standard" that is used for a work around. 2) Is there a way to know which item the mouse is hovering over and put up a display in a tool tip type window. I can't find a way to access the Scollbar to find out the vertical scroll on the window. I would prefer to stay away from a Combo box look as the list control is for display purposes and is not used for selection. Thanks, Marc Tag: Control Addition safety handling Tag: 82185
  - 23
    - Datagrid sorting Is it possible to sort datagrid from code and how? Tnx in advance Tag: Control Addition safety handling Tag: 82182
  - 24
    - embedded resource Hi, How to to create an object (like Cursor) from a .Cur file embedded in a dll of C# classes? Thanks in advance, Pascal Tag: Control Addition safety handling Tag: 82181
  - 25
    - Division By Zero Exception in MonthCalendar.GetMinReqRect(..) Hi all, My prog throw this exception when I add the parent control of the calendar into the main control collection. But It does not throw it at every launch of the application... !!!! So does it means that it's a memory problem or something? I would give any further information if someone could help me out of this :) Thanks in advance! Tag: Control Addition safety handling Tag: 82179
- Next
  - 1
    - monthcalendar Hi, is it possible to display specifik days in another color (red) in the monthcalendar? I know it is possible to display specifik days in bold, but can I change color as well? Thanks Julia Tag: Control Addition safety handling Tag: 82177
  - 2
    - data entry (Visual C++) I built a Winform with several textbox's. I am using sqlDataAdapter. My DataSet is "dsOwnerAnimal1". I have some records in the sql table and I can display them with "Fill, Next and Previous". I clear the DataSet with 'dsOwnerAnimal1->Clear();' and the I enter data into the textbox fields. I then GetChanges and do the update. First I check for changes 'HasChanges' this always fails. Do I need to somehow put the DataSet into insert mode or something? Help!! -- Norm Bohana Tag: Control Addition safety handling Tag: 82176
  - 3
    - Entering Data into a Textbox -- Norm Bohana Tag: Control Addition safety handling Tag: 82175
  - 4
    - sqlDataAdapter Insert C++ I have built a winform project using Visual C++, and I do not know how to build an insert. I cannot find an example or how to code one in the documentation. I can use the fill (sqlDataAdapter2->Fill(dsOwnerAnimal1);). I need help. Norm Bohana Tag: Control Addition safety handling Tag: 82174
  - 5
    - datagrid column headers and size? i have a datagrid that is getting it's dataset from a mysql database. is there a way to change the header label and a way to set each columns width before it is displayed? there are 4 columns being displayed and i need to be able to rename 2 of the columns and set the width of them too. thanx in advance Tag: Control Addition safety handling Tag: 82168
  - 6
    - Shortcut Key question (i.e. "&Submit") I have a Button on a WinForm that has a text property = "&Submit". I noticed that whenever I pressed the "S" key only (without pressing the "Alt" key) the Button's click event would fire. I thought that it was only supposed to fire if the combo "Alt+S" was pressed. My problem is that I have another control (a DataGrid) that is suppoed to respond to the "S" key being pressed and I don't want the Button's click event to be fired. I only want it to be fired if the combo "Alt+S" is pressed. Any suggestions? Tag: Control Addition safety handling Tag: 82167
  - 7
    - A Bug in .NET Framework/Windows Forms Anyone who sees this We have been grappling with this problem ever since we ported to .NET. Microsoft says that MenuItem event handlers are not garbage collected, since they are not "closely tied" to the forms. Although they keep holding the refrence to the forms and it causes the forms to not dispose. So the user objects and GDI object counts keep riising. Apparantly they dont think its an issue and the users have to add handlers for menu item events and then remove the handlers manually. If anyone has come across this issue and know of any other solution besides Microsoft's then please post it. Tag: Control Addition safety handling Tag: 82166
  - 8
    - ICustomTypeDescriptor.GetEditor - Which property am I on?? I have a class that will be edited via the CollectionEditor/CollectionForm UI. To that extent I have defined the various properties I want editable for my class. However, three of the properties are of type string but I would like them edited by selection from a dropdown list whose contents are determined at runtime. It looks like I might be able to use the ICustomTypeDescriptor interface to do what I need. In particular, if I could override the GetEditor method to create a specialized UITypeEditor for these three properties then I think this would do the trick. The only problem is that I cannot see how I know, when GetEditor is being invoked, which property it is being invoked for! Thanks, -- TB Tag: Control Addition safety handling Tag: 82165
  - 9
    - How to select datagrid cell This sounds very simple, but I'm having trouble getting it to work. When I display a WinForms datagrid, I want the value in the first row and column to appear in reverse image. I have tried setting the CurrentCell, focusing the grid, getting the textbox and tried to select the text, etc. Each time with no luck. When I press the Tab key to tab through the cells, then the cells are reverse-imaged. But I need it that way on initial display. Tag: Control Addition safety handling Tag: 82164
  - 10
    - Simple Data Grid DataSource Problem I want to use a data grid in a MFC Project. After adding the grid to an empty dialog, I did not find a way to connect to a data source: The DataSource textbox stays empy (I added all kind of Connections and Commands). The help systems says that ADO is to use, but if found only Microsoft ADO Data Control 6.0 (SP6.0) (OLEDB) and if I add this to the dialog I get: "File or assembly name AxInterop.MSadodclib.dll or dependency was not found". What can I do? Tag: Control Addition safety handling Tag: 82163
  - 11
    - CollectionEditor: How to turn on "description" panel? If I use a PropertyGrid directly, the "description" panel is available and can be turned on and off and resized, etc. But if I use a CollectionEditor, the property grid displayed there doesn't appear to honor the request to display the "description" panel even though the properties of the items in my collection all have description attributes. How can I get the description panel for the property grid portion of the CollectionEditor to be displayed? Thanks! -- TB Tag: Control Addition safety handling Tag: 82161
  - 12
    - CollectionEditor: How to specify arbitary list of values for prope I have a collection of items that I allow the user to edit by bringing up a CollectionEditor. The editor conveniently displays all the properties of my item class and works pretty well. However, I am changing one of the properties from being of an enumerated type to being a string value that should be set from a list of possible values determined at runtime. The enumerated value is automatically handled by the PropertyGrid as a dropdown list. How can I override this behavior to supply the list of allowed values at runtime? I have been successful at plugging in my own derivation of a UITypeEditor for this property but I cannot figure out how to supply the instantiated type editor the list of values to display in the dropdown. Thanks! -- TB Tag: Control Addition safety handling Tag: 82160
  - 13
    - WinForms question... Hi! How do I determine the windows standard vertical scrollbar width in pixels (set from the display properties) from c# code? Peeter. Tag: Control Addition safety handling Tag: 82155
  - 14
    - Scrolling during a Drag Operation Hello all, I have a UserControl that is in a Panel. The Panel's AutoScroll is set to true. When the user drags data over the Panel and hits the edges, I want the control to scroll. I've managed to get this all to work. But I have a few questions: - Is there a standard distance from the edge of the window that the mouse should be before scrolling starts? - How much does one scroll each instance? I've tuned mine to match the speed of the machine I'm doing development work on... Obviously this may not work for others. And one technical question. To do the scrolling I adjust the AutoScrollPosition property while handling the OnDragOver event. If I do this every time the OnDragOver event is fired, my scroll bars move, but nothing is re-drawn (until the scroll bars go as far as they can). On the other hand, if I update the auto scroll position every other time OnDragOver is fired, then everything works as expected: the scroll bars move and the panel is updated. This seems odd, and I find no details on this in the documentation or in a search of the newsgroups. One other question. What is DragDropEeffects.Scroll used for? Is there any point to it? Or is it just there in case you want to change cursors. Finally -- I'm doing my scrolling in OnDragOver. Should I do it in GiveFeedback instead? I'm a little unclear how the framework expects me to seperate the tasks (currently, since I have no special cursors, I do implement GiveFeedback). Cheers, Gordon. Point mouseCurrent = PointToClient(new Point (drgevent.X, drgevent.Y)); /// /// Is it time to scroll (if possible)? Skip every other call to give /// the rest of the update framework a chance to catch up. /// //// _lastDidIt switches from true to false on each call, it is a method variable. int dragboarder = 20; int dragscrolldist = 5; if (mouseCurrent.Y > Height-dragboarder) { if (_lastDidIt) AutoScrollPosition = new Point (-AutoScrollPosition.X, -AutoScrollPosition.Y+dragscrolldist); } if (mouseCurrent.Y < dragboarder) { if (_lastDidIt) AutoScrollPosition = new Point (-AutoScrollPosition.X, -AutoScrollPosition.Y-dragscrolldist); } if (mouseCurrent.X > Width-dragboarder) { if (_lastDidIt) AutoScrollPosition = new Point (-AutoScrollPosition.X+dragscrolldist, -AutoScrollPosition.Y); } if (mouseCurrent.X < dragboarder) { if (_lastDidIt) AutoScrollPosition = new Point (-AutoScrollPosition.X-dragscrolldist, -AutoScrollPosition.Y); } _lastDidIt = !_lastDidIt; /// /// Make sure everything is re-drawn. /// Invalidate(); Tag: Control Addition safety handling Tag: 82150
  - 15
    - Scrolling in DataGridView in Visual Studio 2005 Microsoft has confirmed that this is bug with VS 2005. So we can keep our fingers crossed till they give us the solution. Refer the link for more details http://lab.msdn.microsoft.com/productfeedback/viewfeedback.aspx?feedbackid=2ce60503-bf84-44d0-af9f-ee26b6f1ad21 -- Thanks Arvind Tag: Control Addition safety handling Tag: 82148
  - 16
    - Problem with databinding and RowChanging event I created a method to handle the RowChanging event to validate some data in a databound form. I am using BindingManagerBase.EndCurrentEdit to trigger the RowChanging event. If the data cannot be validated then an exception is raised in the RowChanging event and catched after the call to EndCurrentEdit. The problem I am having is that after calling EndCurrentEdit and raising the exception inside the RowChanging handler, the values in the controls in the form that are not modified again are not fetched again. For example... I have a form with 2 edit boxes which are data bound. Edit1 and Edit2. The original values for each are "mary" and "smith" respectively. If I modify Edit1 to contain "John" and call EndCurrentEdit, the RowChanging event is fired. If I check the Current version of the column it contains "Mary" and the proposed version contains "John". If I raise an exception within the event handler then the data is not saved to the dataset as expected. At this point I still have the edit boxes containing "John" and "Smith"... I am not calling CancelCurrentEdit because I don't want to roll back to the current values... I am simply letting the user know that the data entered is incorrect. If at this point I edit the Edit2 to "Roberts" and call the EndCurrentEdit method, the RowChanging event is fired... but if I check the proposed version of the Edit1 bound column, it contains the Current value "Mary" and NOT the value currently in Edit1. If the user does not edit the Edit1 control directly, the value is not reflected when EndCurrentEdit is called. Thanks, Jeronimo Tag: Control Addition safety handling Tag: 82147
  - 17
    - Design-time control options Hi all, How can I show checkbox for bool properties of my custom control in design-time. The usage of DesignerVerb shows just plain MenuItem. I am wondering how TextBox control shows a CheckBox for MultiLine option. (See a TextBox control and its MultiLine option in VS.NET 2005 Windows Form Design Mode) Yongkee Tag: Control Addition safety handling Tag: 82146
  - 18
    - Webbrowser control + MDI + Disable ctrl-n I am using the Webbrowser control in a MDI application. The Webbrowser control is in a User Control which is loaded into a form. I have implemented IDocHostUIHandler for the User Control and have set the SetUIHandler to the User Control (this). I have also disabled ctrl-n by implementing TranslateAccelerator.The problem is, as the mdi form is loaded initially, I can do ctrl-n and it will popup a new IE browser. Once I click anywhere on the browser, then disables ctrl-n. Any ideas? Tag: Control Addition safety handling Tag: 82145
  - 19
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I was curious about the following scenario but couldn't find the exact
handling using disassembler:

What happens if an instance of a control already added in the Controls
collection of a form is added again? Is there a reference check on each
control addition to handle the said scenario?

It is possible that there is a reference checking since the OnControlAdded
event is not raised for the second time. Anyone who can shed some light on
the said handling? Thanks a lot!

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Re: Control Addition safety handling by Herfried

Herfried
Mon Jan 03 05:30:10 CST 2005

"joeycalisay" <hcalisay@_spamkiller_codex-systems.com> schrieb:
> What happens if an instance of a control already added in the Controls
> collection of a form is added again? Is there a reference check on each
> control addition to handle the said scenario?
>
> It is possible that there is a reference checking since the OnControlAdded
> event is not raised for the second time. Anyone who can shed some light
> on
> the said handling? Thanks a lot!

Yes, the 'Controls' collection checks if the control has already been added
and then adds the control only if it's not already in the collection.

--
M S Herfried K. Wagner
M V P <URL:http://dotnet.mvps.org/>
V B <URL:http://dotnet.mvps.org/dotnet/faqs/>

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