Hi ehsan sadeghi,
Could you please share with us more details regarding the error that appears on your side?
Please try to modify the query in the following way:
refId = Convert.ToInt32(radcmbOperationalBranch.SelectedValue);
query = query.Where(x => x.RefIdOperationBranch == refId);
We are looking forward to hearing from you.
All the best,
the Telerik team
Q1’11 SP1 of Telerik OpenAccess is available for download
; also available is the Q2'11 Roadmap
for Telerik OpenAccess ORM.