selected value does not change in asp:Dropdownlist

Question

I have a simple dropdownlist(ffg)...

<asp:DropDownList   ID="DropDownList2" runat="server"  AutoPostBack="true" BackColor="LightSteelBlue" Font-Size="X-Small"
    OnSelectedIndexChanged="DropDownList2_SelectedIndexChanged1"  Style="z-index: 102; left: 37px; position: absolute; top: 85px" Width="331px"
    </asp:DropDownList>

which I bind data to usind the onpageload event...

DropDownList2.DataSource = td.DataSet
DropDownList2.DataSource = td
DropDownList2.DataTextField = td.Columns("Name").ColumnName.ToString
DropDownList2.DataValueField = td.Columns("VendorCode").ColumnName.ToString
DropDownList2.DataBind()

and an onleselectedindexchaged event where I try to retreive the new value like this...

Protected Sub DropDownList2_TextChanged(ByVal sender As Object, ByVal e As System.EventArgs) Handles DropDownList2.TextChanged
        Dim url As String = "sp_menu.aspx?sp=" & DropDownList2.SelectedValue
        Session.Remove("sp")
        Session("sp") = DropDownList2.SelectedValue
        Session("spnm") = DropDownList2.SelectedItem.Text & " (" & DropDownList2.Text & ")"
        Response.Redirect(url)
    End Sub

But it always brings the first value no matter which one is clicked on the dropdownlist. Please help!

Answer 1

you can try to use

DropDownList2.SelectedItem.Value

instead of

DropDownList2.SelectedItem.Text

Answer 2

Ok... a few things...

First DropDownList2_TextChanged isn't wired to your DropDownList so I can't see how that event would ever fire unless you're doing the wireup in your codebehind

Second

You say this code here

DropDownList2.DataSource = td.DataSet
DropDownList2.DataSource = td
DropDownList2.DataTextField = td.Columns("Name").ColumnName.ToString
DropDownList2.DataValueField = td.Columns("VendorCode").ColumnName.ToString
DropDownList2.DataBind()

is in your PageLoad event. Have you wrapped it in an If Not IsPostBack, because if not, then you'll rebind every time, and lose your previous selection.

Answer 3

When you're databinding in Page_Load, you're essentially also resetting the selecteditem.

You should wrap whatever bindingcode that exists in Page_Load inside an if(!IsPostBack) block.

EDIT: ...or If Not IsPostBack Then ... End If in VB.NET