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POListbox Returns Empty String on SelectedIndexChanged Event
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  1. POListbox Returns Empty String on SelectedIndexChanged Event
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    copied!<p>The above error occurs on a SelectedIndexChanged click event on a listbox.</p> <p>in debug the value returned is "", however when you look at the webpage source code there are definitely values.</p> <p>Here's my listbox:</p> <pre><code>&lt;asp:ListBox ID="lstBxMyList" runat="server" CssClass="binorderlst1" DataTextField="myName" DataValueField="myID" OnSelectedIndexChanged ="lstBxMyList_SelectedIndexChanged" AutoPostBack="true" Rows="10"&gt; &lt;/asp:ListBox&gt; </code></pre> <p>Here's the event:</p> <pre><code>protected void lstBxMyList_SelectedIndexChanged(object sender, EventArgs e) { myID = Convert.ToInt32(lstBxSiteList.SelectedValue.ToString()); ... rest of code } </code></pre> <p>For completeness here's the data binding:</p> <pre><code>private void BindLstBxMyList(int myOtherID) { DataTable dt = new DataTable(); SqlConnection conn; SqlCommand comm; using (conn = new SqlConnection(aSHconns.aconn)) { comm = new SqlCommand("myStoredProc", conn); comm.CommandType = CommandType.StoredProcedure; comm.Parameters.Add(new SqlParameter("@myOtherID", SqlDbType.Int)); comm.Parameters["@myOtherID"].Value = myOtherID; SqlDataAdapter sqlDa = new SqlDataAdapter(comm); try { conn.Open(); sqlDa.Fill(dt); if (dt.Rows.Count &gt; 0) { lstBxMyList.DataSource = dt; lstBxMyList.DataTextField = "myName"; lstBxMyList.DataValueField = "myID"; lstBxMyList.DataBind(); } } finally { conn.Close(); } } } </code></pre> <p>If I revert back to a SqlDataSource the listbox returns values. Bt I need to repopulate the list, so I need the code behind databind (unless there is a better way of course)</p> <p>So why is the listbox selected value returning an empty string? Any help would be gratefully received.</p>
 

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