EntityType 'UserInfo' has no key defined. Define the key for this EntityType.

One or more validation errors were detected during model generation:

 System.Data.Edm.EdmEntityType: : EntityType 'UserInfo' has no key defined. Define the key for this EntityType.  System.Data.Edm.EdmEntitySet: EntityType: EntitySet �UserInfo� is based on type �UserInfo� that has no keys defined.

遇見這個問題，我覺得很奇特，因為事實上我已經為'UserInfo'這個類定義了[KEY]的類注釋。

然后又提示我找不到Key。見下面的代碼

    public class UserInfo
    {
 [Key]  4         public int UserID;  5         public string UserName;
        public string Password;
        public int UseState;
        public string Email;
        public DateTime AddTime;
        public int AddUser_ID;
        public string ImgUrl;
        public virtual UserType UserTypes { get; set; }
    }

后面在stackoverflow上找到了答案。EF會自動識別一個實體的主鍵只要主鍵的名稱符號 'Id'或 '實體名Id'. 另外，它必須聲明成屬性，訪問權限必須是Public的。這個錯誤是因為我將UserId聲明成了一個字段，只要修改成屬性就OK了。修改后的代碼如下所示。

 

    public class UserInfo
    {
        [Key]
        public int UserID { get; set; }
        public string UserName { get; set; }
        public string Password { get; set; }
        public int UseState { get; set; }
        public string Email { get; set; }
        public DateTime AddTime { get; set; }
        public int AddUser_ID { get; set; }
        public string ImgUrl{ get; set; }
        public virtual UserType UserTypes { get; set; }
    }

 

 

 

 

2013-01-10  16:50:05