RadDropDownList items.clear() is not working

[HAN MING]

Hi, 

I trying to do a rest of DropDownList whenever my RadTabStrip is changing. I have try using Items.Clear() when there a TabSwitch Event occur. however, is not wroking.The Item in DropdownList is blinded with Datasource, try setting DataSource as Null is not working too.

Can someone advise my an alternative solution? 

[Ivan Danchev]

Hello Han Ming,

You can clear the DropDownList on tab selection either on the client or on the server. In order to do it on the server subscribe the TabStrip to the TabClick event and call the DropDownList's Clear() method in its handler:

protected void RadTabStrip1_TabClick(object sender, Telerik.Web.UI.RadTabStripEventArgs e)
{
    RadDropDownList1.Items.Clear();
}

On client you can use the OnClientTabSelecting event:

function OnClientTabSelecting(sender, eventArgs) {
    var ddl =  $find("<%=RadDropDownList1.ClientID%>")
    ddl.get_items().clear();
    ddl.get_textElement().innerHTML = "";
}

If you are binding the DropDownList in the code behind, be sure you are not rebinding it after clearing its items, for example after the server-side TabClick fires.

Regards,
Ivan Danchev
Telerik by Progress