LINQ expression node type is not supported in LINQ to Entities

Question

I get an error when I try to run the following query in LINQ to Entities:

 var query = DBConn.myView
                            .Select(dm => new App.DTOs.MyDTO
                            {
                                ID = dm.ID,
                                Prop1 = dm.Prop1
                                ....
                            })
                            .Where(dm => dm.TypeID != 4);

The Error message is:

LINQ expression node type 'TypeID' is not supported in LINQ to Entities

It fails on the .ToList() call:

private List<MyDTO> lstDTO;
lstDTO = query.ToList();

However, if I remove the .Where() from the query, it works. Is there any way to use the Where clause with this query?

Not sure if this question is similar: http://stackoverflow.com/questions/3392612/convert-datatable-to-ienumerablet — John, Sep 24 '12 at 11:36

score 5 · Accepted Answer · edited Sep 24 '12 at 11:40

5

You just need to swap your Select and Where part around:

var query = DBConn.myView
              .Where(dm => dm.TypeID != 4)
              .Select(dm => new App.DTOs.MyDTO
                            {
                                ID = dm.ID,
                                Prop1 = dm.Prop1
                                ....
                            });

edited Sep 24 '12 at 11:40

Andrei

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answered Sep 24 '12 at 11:36

Jamiec

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LINQ expression node type is not supported in LINQ to Entities

1 Answers1