C＃實體框架更新SaveChanges（）不更新數據庫條目

Question

現在正在處理此C＃實體框架更新問題。也許你們中的一個可以看到我失蹤的東西。

問題出在代碼的userEntry部分。我已經追蹤並確保userEntry確實填充了我打算更新的信息。當調用entities.SaveChanges();時，記錄不會在數據庫中更新。

  int userId; 
      using (Entities entities = new Entities()) 
      { 
       MSIFeedStoreData feedStoreEntry = entities.MSIFeedStoreDatas 
        .FirstOrDefault((d) => d.Alias == user.Alias); 

       if (Object.ReferenceEquals(feedStoreEntry, null)) 
       { 
        throw new ArgumentException("The user's alias could not be located in the feed store. The user cannot be added at this time."); 
       } 

       int feedStorePersonnelIdValue; 
       if (Int32.TryParse(feedStoreEntry.PersonellID, out feedStorePersonnelIdValue)) 
       { 
        user.EmployeeId = feedStorePersonnelIdValue; 
       } 
       else 
       { 
        throw new ApplicationException("DATABASE BUG CHECK: An entry was found in the feed store for this user but the personnel ID could not be parsed."); 
       } 

       MSIUser userEntry = entities.MSIUsers 
        .FirstOrDefault((u) => u.EmployeeID == feedStorePersonnelIdValue); 

       if (Object.ReferenceEquals(userEntry, null)) 
       { 
        userEntry = Mapper.Map<MSIUser>(user); 
        userEntry = entities.MSIUsers.Add(userEntry); 
       } 
       else 
       { 
        Mapper.DynamicMap<User, MSIUser>(user, userEntry); 
        entities.MSIUsers.Attach(userEntry); 
       } 

       userId = userEntry.MSIUser_ID; 
       entities.SaveChanges(); 
      } 

      return userId; 
     } 

Answer 1

刪除對Attach的調用，該調用已附加到上下文中。