How to iterate through a listbox

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I have the following code:
sendToAgent.DataSource = someDataSet.Tables[0];
someListBox.DisplayMember = "AGENTNAME";
someListBox.ValueMember = "AGENTID";
someListBox.Tag = "USERNAME";

What I want to do is iterate through the selected values and retrieve the
displaymember, valuemember and Tag.

I saw another post about extracting a DataRowView and using it but it
wouldn't work for me.

I don't understand why this is so arcane.

Any help would be MUCH MUCH appreciated!
Top

Re: How to iterate through a listbox by Bart

Bart
Wed Sep 21 07:57:36 CDT 2005

Hi,

"Dilip M" <DilipM@discussions.microsoft.com> wrote in message
news:1064EAE9-A98A-435C-9961-FC0351AD7549@microsoft.com...
>I have the following code:
> sendToAgent.DataSource = someDataSet.Tables[0];
> someListBox.DisplayMember = "AGENTNAME";
> someListBox.ValueMember = "AGENTID";
> someListBox.Tag = "USERNAME";

First you have "sendToAgent" then "someListBox", is it a typo ? Does the
ListBox have a DataSource?

ListBox.Text will give you the value of the DisplayMember field of selected
row.
ListBox.SelectedValue will give you the value of the ValueMember field of
selected row.
Tag doesn't apply to the items, it only allows you to associate any object
with the ListBox itself.

>
> What I want to do is iterate through the selected values and retrieve the
> displaymember, valuemember and Tag.
>
> I saw another post about extracting a DataRowView and using it but it
> wouldn't work for me.

Yes, but you don't show how you tried it or what went wrong, because if you
bind to a DataTable and allow multiple selection then you need to get the
values through a DataRowView.

foreach ( DataRowView drv in someListBox.SelectedItems )
{
string agentName = (string) drv[someListBox.DisplayMember];
int agentID = (int) drv[someListBox.ValueMember];
string userName = (string) drv[(string)someListBox.Tag];
// ....
}

hth,
greetings

>
> I don't understand why this is so arcane.
>
> Any help would be MUCH MUCH appreciated!


Top

Re: How to iterate through a listbox by DilipM

DilipM
Wed Sep 21 09:00:02 CDT 2005

HI Bart,

Actually it was your post that I mentioned earlier. Thanks very much for
the quick reply!

Yes, 'someListBox' and 'sendToAgent' are the same.

I asumed the Tag value would appy to each item as I need a third field for
this. I guess I'll have to look for a workaround.

I will try this out.

Thanks again!

"Bart Mermuys" wrote:

> Hi,
>
> "Dilip M" <DilipM@discussions.microsoft.com> wrote in message
> news:1064EAE9-A98A-435C-9961-FC0351AD7549@microsoft.com...
> >I have the following code:
> > sendToAgent.DataSource = someDataSet.Tables[0];
> > someListBox.DisplayMember = "AGENTNAME";
> > someListBox.ValueMember = "AGENTID";
> > someListBox.Tag = "USERNAME";
>
> First you have "sendToAgent" then "someListBox", is it a typo ? Does the
> ListBox have a DataSource?
>
> ListBox.Text will give you the value of the DisplayMember field of selected
> row.
> ListBox.SelectedValue will give you the value of the ValueMember field of
> selected row.
> Tag doesn't apply to the items, it only allows you to associate any object
> with the ListBox itself.
>
> >
> > What I want to do is iterate through the selected values and retrieve the
> > displaymember, valuemember and Tag.
> >
> > I saw another post about extracting a DataRowView and using it but it
> > wouldn't work for me.
>
> Yes, but you don't show how you tried it or what went wrong, because if you
> bind to a DataTable and allow multiple selection then you need to get the
> values through a DataRowView.
>
> foreach ( DataRowView drv in someListBox.SelectedItems )
> {
> string agentName = (string) drv[someListBox.DisplayMember];
> int agentID = (int) drv[someListBox.ValueMember];
> string userName = (string) drv[(string)someListBox.Tag];
> // ....
> }
>
> hth,
> greetings
>
> >
> > I don't understand why this is so arcane.
> >
> > Any help would be MUCH MUCH appreciated!
>
>
>
Top

Re: How to iterate through a listbox by Morten

Morten
Wed Sep 21 09:14:42 CDT 2005

Hi Dilip,

There is no problem to read the USERNAME or any other field from the ListBox. Simply use the SelectedItem. When you fill a ListBox with data from a DataTable, the objects that are inserted are DataRowViews, one per row in the DataTable.

DataRowView row = (DataRowView)listBox1.SelectedItem;
string UserName = row["USERNAME"];



On Wed, 21 Sep 2005 16:00:02 +0200, Dilip M"" <DilipM@discussions.microsoft.com> wrote:

> HI Bart,
>
> Actually it was your post that I mentioned earlier. Thanks very much for
> the quick reply!
>
> Yes, 'someListBox' and 'sendToAgent' are the same.
>
> I asumed the Tag value would appy to each item as I need a third field for
> this. I guess I'll have to look for a workaround.
>
> I will try this out.
>
> Thanks again!
>
> "Bart Mermuys" wrote:
>
>> Hi,
>>
>> "Dilip M" <DilipM@discussions.microsoft.com> wrote in message
>> news:1064EAE9-A98A-435C-9961-FC0351AD7549@microsoft.com...
>> >I have the following code:
>> > sendToAgent.DataSource = someDataSet.Tables[0];
>> > someListBox.DisplayMember = "AGENTNAME";
>> > someListBox.ValueMember = "AGENTID";
>> > someListBox.Tag = "USERNAME";
>>
>> First you have "sendToAgent" then "someListBox", is it a typo ? Does the
>> ListBox have a DataSource?
>>
>> ListBox.Text will give you the value of the DisplayMember field of selected
>> row.
>> ListBox.SelectedValue will give you the value of the ValueMember field of
>> selected row.
>> Tag doesn't apply to the items, it only allows you to associate any object
>> with the ListBox itself.
>>
>> >
>> > What I want to do is iterate through the selected values and retrieve the
>> > displaymember, valuemember and Tag.
>> >
>> > I saw another post about extracting a DataRowView and using it but it
>> > wouldn't work for me.
>>
>> Yes, but you don't show how you tried it or what went wrong, because if you
>> bind to a DataTable and allow multiple selection then you need to get the
>> values through a DataRowView.
>>
>> foreach ( DataRowView drv in someListBox.SelectedItems )
>> {
>> string agentName = (string) drv[someListBox.DisplayMember];
>> int agentID = (int) drv[someListBox.ValueMember];
>> string userName = (string) drv[(string)someListBox.Tag];
>> // ....
>> }
>>
>> hth,
>> greetings
>>
>> >
>> > I don't understand why this is so arcane.
>> >
>> > Any help would be MUCH MUCH appreciated!
>>
>>
>>
>



--
Happy coding!
Morten Wennevik [C# MVP]
Top

Re: How to iterate through a listbox by DilipM

DilipM
Wed Sep 21 23:22:01 CDT 2005

Hi Morten,

I am doign a multiselect and trying to loop through the selected values. I
think my biggest confsion was that ListBox.SelectedItems returns a
SelectedObjectCollection.
It is not at all intuitive that it is a bunch of DataRowView items.
Bart's mail earlier cleared that up.

"Morten Wennevik" wrote:

> Hi Dilip,
>
> There is no problem to read the USERNAME or any other field from the ListBox. Simply use the SelectedItem. When you fill a ListBox with data from a DataTable, the objects that are inserted are DataRowViews, one per row in the DataTable.
>
> DataRowView row = (DataRowView)listBox1.SelectedItem;
> string UserName = row["USERNAME"];
>
>
>
> On Wed, 21 Sep 2005 16:00:02 +0200, Dilip M"" <DilipM@discussions.microsoft.com> wrote:
>
> > HI Bart,
> >
> > Actually it was your post that I mentioned earlier. Thanks very much for
> > the quick reply!
> >
> > Yes, 'someListBox' and 'sendToAgent' are the same.
> >
> > I asumed the Tag value would appy to each item as I need a third field for
> > this. I guess I'll have to look for a workaround.
> >
> > I will try this out.
> >
> > Thanks again!
> >
> > "Bart Mermuys" wrote:
> >
> >> Hi,
> >>
> >> "Dilip M" <DilipM@discussions.microsoft.com> wrote in message
> >> news:1064EAE9-A98A-435C-9961-FC0351AD7549@microsoft.com...
> >> >I have the following code:
> >> > sendToAgent.DataSource = someDataSet.Tables[0];
> >> > someListBox.DisplayMember = "AGENTNAME";
> >> > someListBox.ValueMember = "AGENTID";
> >> > someListBox.Tag = "USERNAME";
> >>
> >> First you have "sendToAgent" then "someListBox", is it a typo ? Does the
> >> ListBox have a DataSource?
> >>
> >> ListBox.Text will give you the value of the DisplayMember field of selected
> >> row.
> >> ListBox.SelectedValue will give you the value of the ValueMember field of
> >> selected row.
> >> Tag doesn't apply to the items, it only allows you to associate any object
> >> with the ListBox itself.
> >>
> >> >
> >> > What I want to do is iterate through the selected values and retrieve the
> >> > displaymember, valuemember and Tag.
> >> >
> >> > I saw another post about extracting a DataRowView and using it but it
> >> > wouldn't work for me.
> >>
> >> Yes, but you don't show how you tried it or what went wrong, because if you
> >> bind to a DataTable and allow multiple selection then you need to get the
> >> values through a DataRowView.
> >>
> >> foreach ( DataRowView drv in someListBox.SelectedItems )
> >> {
> >> string agentName = (string) drv[someListBox.DisplayMember];
> >> int agentID = (int) drv[someListBox.ValueMember];
> >> string userName = (string) drv[(string)someListBox.Tag];
> >> // ....
> >> }
> >>
> >> hth,
> >> greetings
> >>
> >> >
> >> > I don't understand why this is so arcane.
> >> >
> >> > Any help would be MUCH MUCH appreciated!
> >>
> >>
> >>
> >
>
>
>
> --
> Happy coding!
> Morten Wennevik [C# MVP]
>
Top

Re: How to iterate through a listbox by WhiskeyRomeo

WhiskeyRomeo
Sat Aug 25 14:10:01 CDT 2007

Thank you for this solution. I wasted so much time searching Microsoft's
documentation. I should have come here first. How hard would it have been
to include a "How to iterate selected items in a ListBox" topic in help?

WR

"Bart Mermuys" wrote:

> Hi,
>
> "Dilip M" <DilipM@discussions.microsoft.com> wrote in message
> news:1064EAE9-A98A-435C-9961-FC0351AD7549@microsoft.com...
> >I have the following code:
> > sendToAgent.DataSource = someDataSet.Tables[0];
> > someListBox.DisplayMember = "AGENTNAME";
> > someListBox.ValueMember = "AGENTID";
> > someListBox.Tag = "USERNAME";
>
> First you have "sendToAgent" then "someListBox", is it a typo ? Does the
> ListBox have a DataSource?
>
> ListBox.Text will give you the value of the DisplayMember field of selected
> row.
> ListBox.SelectedValue will give you the value of the ValueMember field of
> selected row.
> Tag doesn't apply to the items, it only allows you to associate any object
> with the ListBox itself.
>
> >
> > What I want to do is iterate through the selected values and retrieve the
> > displaymember, valuemember and Tag.
> >
> > I saw another post about extracting a DataRowView and using it but it
> > wouldn't work for me.
>
> Yes, but you don't show how you tried it or what went wrong, because if you
> bind to a DataTable and allow multiple selection then you need to get the
> values through a DataRowView.
>
> foreach ( DataRowView drv in someListBox.SelectedItems )
> {
> string agentName = (string) drv[someListBox.DisplayMember];
> int agentID = (int) drv[someListBox.ValueMember];
> string userName = (string) drv[(string)someListBox.Tag];
> // ....
> }
>
> hth,
> greetings
>
> >
> > I don't understand why this is so arcane.
> >
> > Any help would be MUCH MUCH appreciated!
>
>
>
Top