This demo illustrates how to filter RadGrid by using RadFilter embeded in RadWindow.
RadFilter is placed inside ContentTemplate of modal RadWindow.
The controls inside RadWindow ContentTemplate can be used as part of the same page in which it is declared.
Thus RadFilter can be accessed directly and ajaxified as follow:
<telerik:AjaxSetting AjaxControlID="RadFilter1">
<UpdatedControls>
<telerik:AjaxUpdatedControl ControlID="RadFilter1" />
</UpdatedControls>
</telerik:AjaxSetting>
To show the RadFilter control, right click on the RadGrid header and choose the "Show filter" option or click on the button in the GridCommandItemTemplate.
A modal RadWindow containing the RadFilter will be opened.