c# - Alternative to ASP.NET drop down list -

regardless of or try drop down list isn't working,

<asp:dropdownlist id="drop1" runat="server" autopostback="true" enabledviewstate="true" onclick="drop1_selectedindexchanged" /> 

bind here,

  protected void page_load(object sender, eventargs e)         {             if (!ispostback)             {                 binddropdownlist();             }             //drop1.selectedindexchanged += new eventhandler(drop1_selectedindexchanged);         } 

and here's method, never triggers (i use break point check)

protected void drop1_selectedindexchanged(object sender, eventargs e) {     //checkboxlist1.items.add("hahahha"); } 

is there alternative ?????????? need populate drop down list using,

 using (sqldatasource ds = new sqldatasource(connectionstring(), selectcommand()))             {                 system.data.dataview dv = (system.data.dataview)ds.select(datasourceselectarguments.empty);                 if (dv.count > 0)                 {                     drop1.datasource = ds;                     drop1.datatextfield = "username";                     drop1.databind();                     drop1.items.insert(0, "please select username ");                 }             } 

there no click event defined dropdownlist. event use selectedindexchanged:

<asp:dropdownlist id="drop1" runat="server"                   autopostback="true"                   enabledviewstate="true"                   onselectedindexchanged="drop1_selectedindexchanged" />