Cannot find Entity Framework 4 annotations

问题

I'm trying to map a POCO class to a table of my DB using annotation. I need to use Table annotation to specify the name of my table, but I cannot resolve the Table annotation.

Note: I imported System.Data.Entity namespace but It doesn't work.

Which namespace do I have to import to use EF annotations?

NOTE 1 I mean:

[Table("my_table")]
public class MyClass
{
    // ...
}

NOTE 2 My Entity Framework dll is v4.0.30319

回答1:

I need to use the Table annotation

You need to import the System.Data.Linq library, the TableAttribute can be referenced from the System.Data.Linq.Mapping namespace.

回答2:

You should import the System.ComponentModel.DataAnnotations namespace.

edit for .net 4.5 and EF 5.0: you should use System.ComponentModel.DataAnnotations.Schema.Table Attribute

回答3:

using System.ComponentModel;

and

[DisplayName("My friendly table name")]

Are sufficient to make it work with EF 5/6 and .Net 4.5, no need for System.ComponentModel.DataAnnotations namespace nor System.Data.Linq for these versions.

来源：https://stackoverflow.com/questions/13340733/cannot-find-entity-framework-4-annotations