How do your read selected values from a BOUND ListBox in VB.Net

25 May 2005 8:15 PM

Richard Albrecht

I have been trying to figure out for days on how to read values from a Bound
ListBox. The listBox gets the values from an Access Table.

I can read values fine for Non-Bound ListBoxes, But the same code doesn't
work for Bound, see below:

Any one of these work for a non-bound listbox.

Code:
'This get all items
    For lnCnt = 0 To lstVolIssue.Items.Count - 1
      lsVolIssue &= lstVolIssue.Items(lnCnt) & ","
    Next

    'These 2 methods get only the selected
    For Each lsStr In lstVolIssue.SelectedItems
      lsVolIssue &= lsStr.ToString
    Next

    For lnCnt = 0 To lstVolIssue.SelectedIndices.Count - 1
      lsVolIssue = lsVolIssue &
lstVolIssue.Items(lstVolIssue.SelectedIndices.Item(lnCnt)).ToString & ","
    Next

When using a BOUND listbox the 1st Code Segment

Code:

    'This get all items
    For lnCnt = 0 To lstVolIssue.Items.Count - 1
      lsVolIssue &= lstVolIssue.Items(lnCnt) & ","
    Next

Throws This exception
Cast from type 'DataRowView' to type 'String' is not valid.

The Second Code Segment

Code:

    'These 2 methods get only the selected
    For Each lsStr In lstVolIssue.SelectedItems
      lsVolIssue &= lsStr.ToString
    Next

Throws the same exception
Cast from type 'DataRowView' to type 'String' is not valid.

And the third segment

Code:

    For lnCnt = 0 To lstVolIssue.SelectedIndices.Count - 1
      lsVolIssue = lsVolIssue &
lstVolIssue.Items(lstVolIssue.SelectedIndices.Item(lnCnt)).ToString & ","
    Next

Returns
System.Data.DataRowView,System.Data.DataRowView,System.Data.DataRowView,System.Data.DataRowView,

So it has to do with it being bound to a select statement that populates the
list.

HELP!!!

Richard

25 May 2005 8:29 PM

Rick Rothstein

Almost everybody in this newsgroup is using VB6 or lower. While you may
get a stray answer to VB.NET (including VB2003 and VB2005 which has
dropped .NET from its name) questions here, you should ask them in
newsgroups devoted exclusively to .NET programming. Look for newsgroups
with either the word "dotnet" or "vsnet" in their name.

For the microsoft news server, try these newsgroups for Visual Basic
..NET related questions...

   microsoft.public.dotnet.languages.vb
   microsoft.public.dotnet.languages.vb.upgrade
   microsoft.public.dotnet.languages.vb.controls
   microsoft.public.dotnet.languages.vb.data

And these for more general .NET questions

   microsoft.public.dotnet.general
   microsoft.public.vsnet.general

Note: There are many other .NET newgroups (use the first three "fields"
from the last two as templates when searching for them), but the above
ones should get you started.

Rick - MVP

Show quoteHide quote

"Richard Albrecht" <RichSpamNotWanted@RAlbrecht.net> wrote in message
news:N15le.1687$uu.1456@newssvr33.news.prodigy.com...
> I have been trying to figure out for days on how to read values from a
Bound
> ListBox. The listBox gets the values from an Access Table.
>
> I can read values fine for Non-Bound ListBoxes, But the same code
doesn't
> work for Bound, see below:
>
> Any one of these work for a non-bound listbox.
>
>
> Code:
> 'This get all items
>     For lnCnt = 0 To lstVolIssue.Items.Count - 1
>       lsVolIssue &= lstVolIssue.Items(lnCnt) & ","
>     Next
>
>     'These 2 methods get only the selected
>     For Each lsStr In lstVolIssue.SelectedItems
>       lsVolIssue &= lsStr.ToString
>     Next
>
>     For lnCnt = 0 To lstVolIssue.SelectedIndices.Count - 1
>       lsVolIssue = lsVolIssue &
> lstVolIssue.Items(lstVolIssue.SelectedIndices.Item(lnCnt)).ToString &
","
>     Next
>
>
>
>
>
>
> When using a BOUND listbox the 1st Code Segment
>
>
> Code:
>
>     'This get all items
>     For lnCnt = 0 To lstVolIssue.Items.Count - 1
>       lsVolIssue &= lstVolIssue.Items(lnCnt) & ","
>     Next
>
>
>
>
> Throws This exception
> Cast from type 'DataRowView' to type 'String' is not valid.
>
> The Second Code Segment
>
>
> Code:
>
>     'These 2 methods get only the selected
>     For Each lsStr In lstVolIssue.SelectedItems
>       lsVolIssue &= lsStr.ToString
>     Next
>
>
>
>
> Throws the same exception
> Cast from type 'DataRowView' to type 'String' is not valid.
>
> And the third segment
>
>
> Code:
>
>     For lnCnt = 0 To lstVolIssue.SelectedIndices.Count - 1
>       lsVolIssue = lsVolIssue &
> lstVolIssue.Items(lstVolIssue.SelectedIndices.Item(lnCnt)).ToString &
","
>     Next
>
>
>
>
> Returns
>

System.Data.DataRowView,System.Data.DataRowView,System.Data.DataRowView,
System.Data.DataRowView,
Show quoteHide quote

>
> So it has to do with it being bound to a select statement that
populates the
> list.
>
> HELP!!!
>
> Richard
>
>