dorpdownlist SelectedIndexChanged breakpoint not trigged

Question

I have a breakpoint on a dropdownlist control on my asp.net page. But it is not activated when I select an item from the ListBox. What am I missing here?

onselectedindexchanged="ddlProjectSearchID_SelectedIndexChanged"  

protected void ddlProjectSearchID_SelectedIndexChanged(object sender, EventArgs e)
{
    ClientScript.RegisterClientScriptBlock(typeof(string), "key", string.Format("alert('{0}');", DateTime.Now.Day), true);
}

Answer 1

Set AutoPostBack="true" on DropDown.