I have a RadGrid with a user control for the edit form. The user control contains a RadDatePicker control. When the form is in add mode, everything works fine. When it is edit mode and and I click on the datepicker control, I receive a Microsoft JScript runtime error: Object expected error.
Thank you for contacting us and I'm sorry for the delayed response.
May I suggest that you verify there is a property called DataItem in your user control. Please review this link and this demo which describe how to use a user control as an edit template. For your convenience I attached a working test project which implements your scenario.
I hope these directions are helpful. Let me know how it goes.
Best wishes,
Georgi Krustev
the Telerik team
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