如何枚举属性实体框架图4 [英] How to map an enum property in Entity Framework 4

问题描述

我的模型有一个属性，它是一个枚举：

My model has a property that is an enumeration:

Sql server column "user_status" is a int NOT NULL.

[Column("User_Status")]
public UserStatus UserStatus { get; set; }

public enum UserStatus
{
    Pending  = 1,
    Member = 2,
    Banned   = 3
}

目前，我得到一个错误，当我保存实体，因为它说，该列user_status不能为null。

Currently I am getting an error when I save the entity because it says the column user_status cannot be null.

我怎样才能得到实体框架时，它保存/更新此属性转换为int，而当它加载的实体将它转换为枚举。

How can I get entity framework to convert this property to an Int when it saves/updates, and when it loads the entity it converts it to the enum.

推荐答案

实体框架4不支持使用枚举列类型。如果你想为枚举的原生支持，你需要升级到实体框架5。

Entity Framework 4 does not support using enums as column types. If you want to have native support for enums, you'll need to upgrade to Entity Framework 5.

如果你绝对必须使用（因为这是已经在实施了一个项目）EF 4，那么我建议你围绕它去像这样：

If you absolutely have to use EF 4 (because of a project that's already been implemented in it), then I recommend that you go around it as so:

[Column("User_Status")]
public int UserStatusAsInt { get; set; }

[NotMapped]
public UserStatus UserStatus
{
  get { return (UserStatus) this.UserStatusAsInt; }
  set { this.UserStatusAsInt = (int)value; }
}

这不是一个pretty的解决方案，但它是一个坚实的解决方法的问题，你仍然可以绑定到它在您的网页，并把它作为枚举本身在其他code

It's not a pretty solution, but it's a solid workaround to the problem, and you still get to bind to it on your pages and treat it as the enum itself in your other code.

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