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return GUID

Posted By:      Posted Date: August 28, 2010    Points: 0   Category :ASP.Net
Hi,I am using LINQ.I have 2 methods.Method 1public Guid getUserIDByProfileCode(string pCode) { var user = from p in dc.OtherProfiles where p.ProfileCode == pCode select p.UserId; return user.FirstOrDefault(); }Method 2 public Guid getStudentUserId(int id) { var stdID = from p in dc.StudentProfiles where p.ID == id select p.UserId; return stdID.FirstOrDefault(); }The first method is ok. But the second method says "Can not implicitly convert System.GUID? to System.GUID. An explicit conversion exists (Are you missing a cast?)"What is the difference between these 2 mehtods?? how can I solve it?Error 2 Cannot implicitly convert type 'System.Guid?' to 'System.Guid'. An explicit conversion exists (are you missing a cast?) C:\WebDevelopment\DrivingSchool\DrivingSchool\BLL\RegistrationBLL.cs 150 20 DrivingSchool

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