title: Selected item in list box is null
body: <p>I have few items in the listbox. When I select an item, I store it in a string for further use, but when I display that string value it is shown as null.</p>
  
  <p>Below is the code for my Invitee.aspx file:</p>
  
  <pre><code>&lt;%@ Page Language="C#" AutoEventWireup="true" CodeBehind="Invitee.aspx.cs" Inherits="FinalProj2.Invitee" %&gt;
  
  &lt;!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"&gt;
  
  &lt;html xmlns="http://www.w3.org/1999/xhtml"&gt;
  &lt;head runat="server"&gt;
      &lt;title&gt;&lt;/title&gt;
  &lt;/head&gt;
  &lt;body&gt;
      &lt;form id="form1" runat="server"&gt;
      &lt;div&gt;
  
          &lt;asp:DropDownList ID="DropDownList1" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
          &lt;asp:DropDownList ID="DropDownList2" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
          &lt;asp:DropDownList ID="DropDownList3" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
  &amp;nbsp;&amp;nbsp;&amp;nbsp;&amp;nbsp;
          &lt;asp:DropDownList ID="DropDownList4" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
          &lt;asp:DropDownList ID="DropDownList5" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
          &lt;asp:DropDownList ID="DropDownList6" runat="server"&gt;
          &lt;/asp:DropDownList&gt;
  
      &lt;/div&gt;
      &lt;asp:ListBox ID="ListBox1" runat="server" AutoPostBack="true" Height="310px" 
          onselectedindexchanged="ListBox1_SelectedIndexChanged" Width="271px"&gt;
      &lt;/asp:ListBox&gt;
      &lt;asp:TextBox ID="TextBox1" runat="server" Height="217px" Width="544px"&gt;&lt;/asp:TextBox&gt;
      &lt;/form&gt;
  &lt;/body&gt;
  &lt;/html&gt;
  </code></pre>
  
  <p>And code for Invitee.aspx.cs:</p>
  
  <pre><code>using System;
  using System.Collections.Generic;
  using System.Linq;
  using System.Web;
  using System.Web.UI;
  using System.Web.UI.WebControls;
  
  namespace FinalProj2
  {
      public partial class Invitee : System.Web.UI.Page
      {
          FinalProj2.Models.DataClasses1DataContext db = new FinalProj2.Models.DataClasses1DataContext();
  
          protected void Page_Load(object sender, EventArgs e)
          {
  
              for (int i = 1; i &lt; 13; i++)
              {
                  DropDownList1.Items.Add(new ListItem(i.ToString()));
                  DropDownList4.Items.Add(new ListItem(i.ToString()));
              }
  
              for (int i = 1; i &lt; 32; i++)
              {
                  DropDownList2.Items.Add(new ListItem(i.ToString()));
                  DropDownList5.Items.Add(new ListItem(i.ToString()));
              }
  
              for (int i = 2010; i &lt; 2021; i++)
              {
                  DropDownList3.Items.Add(new ListItem(i.ToString()));
                  DropDownList6.Items.Add(new ListItem(i.ToString()));
              }
  
  
              var query = from emp in db.Employees
                          select emp.Employee_Name;
  
              ListBox1.DataSource = query;
              ListBox1.DataBind();
          }
  
          protected void ListBox1_SelectedIndexChanged(object sender, EventArgs e)
          {
              Response.Write("Hello");
  
              string selected = ListBox1.SelectedValue.ToString();
  
              Response.Write("\n Selected Value is" + selected);
  
              var query = from emp in db.Employees
                          where emp.Employee_Name == selected
                          select emp.Employee_ID;
  
              Response.Write(query);
  
              //int empid = query.First();
  
              //var query1 = from meet_emp in db.Meet_Emps
              //             where meet_emp.Employee_ID == empid
              //             select meet_emp.Meeting_ID;
  
              //int meetid = query1.First();
  
              //Response.Write(meetid);
          }
      }
  }
  </code></pre>
  
  <p>Value of string "selected" is null after I select an item in list box.</p>