Thank you for contacting us.
Currently, there is no more convenient approach than the suggested one:
filter = $find(
"<%= RadFilter1.ClientID %>"
You can also access and traverse the expressions collection object:
Or get the OrderIndex of the expression by its element id:
Additionally, please note that for the coming Q2 2013 release, our developers have re-builded the RadFilter control which will expose many new properties and will provide richer and much more convenient interface to be customized.
Hope this helps.
All the best,
the Telerik team
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