2011-10-25 109 views
1

當我使用此代碼更新CustomerName時,CustomerDesc變爲NULL,反之亦然。我實現找到了解決辦法在 EF4 Update Entity Without First Getting Entity在EF4無法更新沒有第一個實體的實體

using (var dbMdl = new TestDBEntityModel()) 
    { 

     Customer pr1 = new Customer(); 
     pr1.CustomerId = 1; 
     if(pr1.EntityState == EntityState.Detached) 
      dbMdl.Customers.Attach(pr1); 
     // pr1.CustomerName = "Changed!"; 
     pr1.CustomerDesc = "Changed!"; 
     dbMdl.ObjectStateManager.ChangeObjectState(pr1,  System.Data.EntityState.Modified); 
     dbMdl.SaveChanges(); 

    } 

回答

0

通過網上教程去後,我解決它通過消除dbMdl.ObjectStateManager.ChangeObjectState(pr1, System.Data.EntityState.Modified);和它的工作如預期。