How can i fix "LINQ to Entities does not recognize the method" error

Question

I got LINQ to Entities does not recognize the method 'System.String GetName(System.Type, System.Object)' method, and this method cannot be translated into a store expression.

How can i fix that? I did not find a suitable example for my case.

 return context.Books.Select(e => new BookViewModel
            {
                BookId = e.BookId,
                BookName = e.BookName,
                Genre = new GenreViewModel
                { GenreName = Enum.GetName(typeof(Genre), (int)e.Genre), GenreId = (int)e.Genre },// error is here
                Pages = e.Pages,
                Publisher = e.Publisher,
                Authors = e.Authors.Select(t => new AuthorViewModel
                {
                    AuthorId = t.AuthorId,
                    AuthorName = t.AuthorName
                }).ToList()
            });

Models:

public enum Genre
{
[Description("Comedy")]
Comedy,
[Description("Drama")]
Drama,
[Description("Horror")]
Horror,
[Description("Realism")]
Realism,
[Description("Romance")]
Romance,
[Description("Satire")]
Satire,
[Description("Tragedy")]
Tragedy,
[Description("Tragicomedy")]
Tragicomedy,
[Description("Fantasy")]
Fantasy,
[Description("Mythology")]
Mythology,
[Description("Adventure")]
Adventure,
}
public class GenreViewModel
{
        public int GenreId { get; set; }
        public string GenreName { get; set; }
}

Possible duplicate of [LINQ to Entities does not recognize the method](https://stackoverflow.com/questions/7259567/linq-to-entities-does-not-recognize-the-method) — Rai Vu, Mar 05 '18 at 07:38
Depending on your EF version you can probably just do `e.Genre.ToString()`. — Gert Arnold, Mar 05 '18 at 08:01

score 4 · Accepted Answer · answered Mar 05 '18 at 08:07

4

The easiest way is probably to use a simple getter for GenreName in your ViewModel

public class GenreViewModel
{
        public int GenreId { get; set; }
        public string GenreName { get{ return Enum.GetName(typeof(Genre), GenreId);}}
}

So you don't need to put this in the Select clause.

answered Mar 05 '18 at 08:07

Raphaël Althaus

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Thank you a lot, this is really a very simple and effective solution) – Vlad Mar 05 '18 at 08:17

How can i fix "LINQ to Entities does not recognize the method" error

1 Answers1