how to populate asp:DropDownList from C# side
<p>I am trying to populate asp:DropDownList with data items and here is the code i have written so far</p>

<p>.aspx side</p>

<pre><code>&lt;asp:DropDownList ID="ddl" runat="server" /&gt;
</code></pre>

<p>C# side</p>

<pre><code>protected void btnAdd_Click(object sender, EventArgs e)
{
  ddl.DataTextField = "hello";
  ddl.DataTextField = "2";
  ddl.DataBind();
}
</code></pre>

<p>The method <code>btnAdd_Click</code> is invoked. I tested it. But the data list is not getting populated with those data items.</p>
