使用属性扩展 c# 中的类

Question

I use Entity framework 6 (database first) in my mvc project. The database has a table called User which has columns like name, adress, email. In my project I therefore have the User.cs class auto generated in my project. I need to extend that user class with some properties. Should I create this in order to extend the class with this prpoerty..?

    public partial class User
{
    public bool SomeBoolProperty { get; set; }
}

If so where do I add it? I tried to add it under a folder called partials\\user.cs but when doing so this property is not available when looking at what properties is available.

Answer 1

You can have a child class derived from User class .

Ex:

public class childClass:User
{
   public bool SomeBoolProperty { get; set; }
}

You can access these property like this

User _user= new ChildClass();
_user.SomeBoolProperty =10;

Answer 2

It's possible that when you add the partial class in your "Partial" folder, Visual Studio adds .Partials to the namespace of the partial class you add, because the convention is that namespaces should follow the folder path. In that case, the compiler won't join the auto-generated class with the partial class you created, because they are in different namespaces.

Make sure the namespace is the same in your partial class and the generated class.

Answer 3

You need to make sure that the namespace that you specify for your hand-written partial class User is exactly the sam e as that of the EF6-generated partial class User . If the namespaces between the two are different then the partial classes will not be put together, they will stay separate.

Answer 4

In your User.cs you can add properties that won't be mapped to the database by using the [NotMapped] attribute above your properties:

public class User
{
    //Your autogenerated properties

    [NotMapped]
    public bool SomeBoolProperty { get; set; }

    [NotMapped]
    public int AnotherProperty { get; set; }
}