VS 2010 - SelectedValue Of ListBox Always Null
Sep 29, 2011
I got this in my page:
Code:
<asp:ListBox runat="server" ID="lstCategories" SelectionMode="Single"></asp:ListBox>
I populate it in my code-behind correctly, and when I look at the generated source it's:
Code:
<option value="1">aaaa</option>
<option value="2">bbbb</option>
However, in my button click event, when I check waht is the selected item's value (lstCategories.SelectedItem.Value, also lstCategories.SelectedValue) I find that the selected item is always null.
the user can only select one item in the list for what it matters. (SelectionMode = Single)
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The script below is what i have done so far.
Partial Class _Default
Inherits System.Web.UI.Page
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Dim SwapN0 As Integer
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Next
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End Sub
End Class
=======================================
Sub UpdateSwap(ByVal valueA As String, ByVal ValueBAs String, ByVal ValueC As Integer, ByVal ValueD As Date)
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[code]....
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Code:
[code]....
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