Reload combobox on parent page on closing Radwindow
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I am having textbox ,combobox & button controls in an aspx page.To add a new value in the combobox,I am using a button.Onclick of this 
 Button ,a radwindow opens which add/update some records.On closing the radwindow,I need to reflect those records in the parent page combobox.
For this,I have used onclientclose property of radwindow  with "window.location.reload();".If the user has entered some data in other controls before clicking the radwindow button,then all data will be lost.I just need to reload the combobox on closing the radwindow.
Please suggest your ideas.
My code is as below:

    <telerik:RadWindow ID="NationalityDialog" Title="Nationality Data" runat="server" Behaviors="Close" Height="550px" Width="450px"
                    Left="150px" OnClientClose="NationClientClose" />
    
    function NationClientClose(sender, args) {
                        window.location.reload();
    	//window.location.href = window.location.href; 
                    }

Thanks,
Soumya