Items Doubled in DropDownList

BobRoberts · November 1st, 2011, 01:08 PM

I've encountered a problem that seems to have me stuck. I have a DropDownList3 that gets filtered by the values of two other dropdownlists ( 1 and 2) on the form. DropDownlist3 should show:

--- Select Item ---
AAAAAAAAAAAAAA
BBBBBBBBBBBBBBBB

But instead it shows:

--- Select Item ---
AAAAAAAAAAAAAA
BBBBBBBBBBBBBBBB
AAAAAAAAAAAAAA
BBBBBBBBBBBBBBBB

It seems perfectly functional otherwise. Now if I take away the AppendDataBoundItems="True", then it shows only two items, but it does not show the --- Select Item --- at the top, which prevents the AAAAAAAAAA SelectedIndexChanged event from firing when you click the top item. The same is true if I remove the "<asp:ListItem Value="">--- Select Item ---</asp:ListItem>".

Here is the code:

Code:

 <asp:Label id="ItemId" AssociatedControlId="DropDownList3" Text="Item: " runat="server" />
        <asp:DropDownList ID="DropDownList3" runat="server" 
    DataSourceID="SqlDataSource3" DataTextField="ITEM_DESCR" 
    DataValueField="ID_KEY" AutoPostBack="True" 
    onselectedindexchanged="DropDownList3_SelectedIndexChanged" 
          AppendDataBoundItems="True" CssClass="RightMargin">
    <asp:ListItem Value="">--- Select Item ---</asp:ListItem>
  </asp:DropDownList>



<asp:SqlDataSource ID="SqlDataSource3" runat="server" 
    ConnectionString="<%$ ConnectionStrings:BCConnectionString %>" 
             
    SelectCommand="SELECT [ITEM_DESCR], [ITEM_ID], [HEADING], [SUB_HEADING], [ID_KEY] FROM [QPURCH] WHERE (([EMP_NAME] = 

@userName) AND ([FORM_NAME] = @FORM_NAME) AND ([DEPT] = @DEPT)) ORDER BY [HEADING], [SUB_HEADING], [ITEM_DESCR]" 
    onselecting="SqlDataSource3_Selecting"> 
          
    <SelectParameters>
      <asp:Parameter Name="UserName" Type="String" />
      <asp:ControlParameter ControlID="DropDownList2" Name="FORM_NAME" 
        PropertyName="SelectedValue" Type="String" />
      <asp:ControlParameter ControlID="DropDownList1" Name="DEPT" 
        PropertyName="SelectedValue" Type="String" />
    </SelectParameters>

  </asp:SqlDataSource>

BobRoberts · November 1st, 2011, 01:48 PM

After searching for awhile and trying several things out, I think I found the solution: I removed the AppendDataBoundItems="True" from the control, and put the following in the DropDownList3 DataBound event code-behind:

Code:

    if (DropDownList3.Items.Count > 0)
    {
      DropDownList3.Items.Insert(0, "--- Select Item ---");
      DropDownList3.Items[0].Value = "";
      DropDownList3.SelectedIndex = 0;

    }