CODEWITHSUNDEEP
c#.netlinqentity-framework
Null Reference
Null Reference

Reputation: 11360

Cannot compare elements of type. Only primitive types, enumeration types and entity types are supported

I've read here and here, but I still can't figure why I'm getting this error. both c.NvrId and n.Id are of type int

var cameras = from c in context.CameraEntities
              join n in context.NetworkVideoRecorderEntities
                  on c.NvrId equals n.Id
                  into cn
              from x in cn.DefaultIfEmpty()
              where listofIds.Contains(c.Id)
              select new Camera
              {
                  Id = c.Id,
                  Name = c.Name,
                  NetworkVideoRecorder = cn == null ? null : new NetworkVideoRecorder
                  {
                      Id = x.Id,
                      Description = x.Description,
                      IP = x.IP,
                  }
              };

return cameras.ToList();

Error gets thrown when I perform a cameras.ToList();

This is the full error message:

Cannot compare elements of type 'System.Collections.Generic.IEnumerable`1[[Models.NetworkVideoRecorderEntity, Asis.Ibss.Net.DataObjects, Version=2014.1.5494.33354, Culture=neutral, PublicKeyToken=null]]'. Only primitive types, enumeration types and entity types are supported.

Upvotes: 1

Views: 4138

Answers (1)

Amadeus Sanchez
Amadeus Sanchez

Reputation: 2585

You were doing a null check within the 'select' clause.

NetworkVideoRecorder = cn == null ? null : new NetworkVideoRecorder { Id = x.Id, Description = x.Description, IP = x.IP, }

As @RahulSingh pointed out in the comments, I think you are better off checking if x is null rather than checking if cn is null.

Upvotes: 1

Related Questions