LINQ to Entities only supports casting EDM primitive or enum

Question

Hi,

 

Below is my code. I am assign a class member in linq where the data type is "AnswerType". During run time i got the error message as "LINQ to Entities only supports casting EDM primitive or enumeration types".

 

Below is my model class QuestionModel 

 

public class QuestionModel

{

public int QuestionId { get; set; }

public AnswerType AnswerType { get; set; }

public List<AnswerOption> AnswerOptions { get; set; }

}

 

Below is my model class AnswerType

public class AnswerType

{

public int Id { get; set; }

public string Description { get; set; }

} 

 

Below is my Controller class method

 

List<QuestionModel> questions = new List<QuestionModel>();

var questionList = PoletusHrSuiteContext.Questions

.Where(question => question.ClientInterviewingPositionId == interviewInformaton.InterviewingPosition.InterviewingPositionId)

.Select (question => new Models.QuestionModel {

QuestionId = question.QuestionId,

AnswerType = (Models.AnswerType) (from mapping in PoletusHrSuiteContext.QuestionAnswerTypeMappings

join answerType in PoletusHrSuiteContext.AnswerTypes on mapping.AnswerTypeId equals answerType.AnswerTypeId

where question.QuestionId == mapping.QuestionId

select new Models.AnswerType { Id = answerType.AnswerTypeId, Description = answerType.AnswerTypeDescription })

});

questions = questionList.ToList();

 

Below is error message i am during run-time.

Unable to cast the type 'System.Linq.IQueryable`1[[Models.AnswerType, Models, Version=1.0.0.0, Culture=neutral, PublicKeyToken=null]]' to type 'Models.AnswerType'. LINQ to Entities only supports casting EDM primitive or enumeration types.

 

How to overcome this issue?

Thanks in advance for the solving this issue.