I have the following code:
return this.ObjectContext.BranchCostDetails.Where( b => b.TarrifId == tariffId && b.Diameter == diameter || (b.TarrifId==tariffId && !string.IsNullOrWhiteSpace(b.Diameter)) || (!b.TarrifId.HasValue) && b.Diameter==diameter);
And I get this error when I try to run the code:
LINQ to Entities does not recognize the method 'Boolean
IsNullOrWhiteSpace(System.String)' method, and this method cannot be
translated into a store expression."
How can I solve this problem and write code better than this?