更新在LINQ2SQL记录与RECORDTYPE

Question

以下简化代码无法正常工作（因为它设置检索对象引用参数）的对象，但它显示了我想要做的

public bool updateEvent(clubEvent newEvent) 
    { 
     TNightCon tCon = new TNightCon(); 
     clubEvent cEv = (from cEvent in tCon.clubEvents 
         where cEvent.EventID == newEvent.EventID 
         select cEvent).First(); 

     // Won't work, but do I have to set all the fields manually? 
     cEv = newEvent; 
     tCon.SubmitChanges(); 
     return true; 
    } 

Answer 1

您不需要检索当前对象来执行您需要执行的操作。如果ID相同，则只需将新对象附加到上下文中即可。这个技巧就变成了让Linq2SQL将对象视为“脏”。 Timothy Khouri有a blog post，详细介绍了在上下文中使用Refresh方法的有用技巧。这是它的样子。

public bool updateEvent(clubEvent newEvent) 
    { 
     tCon.clubEvents.Attach(newEvent); 
     tCon.Refresh(RefreshMode.KeepCurrentValues, settings) 
     tCon.SubmitChanges(); 
     return true; 
    } 

Answer 2

或者，或者，

tCon.ClubEvents.DeleteOnSubmit(cEv); 
    tCon.CLubEvents.InsertOnSubmit(newEvent); 
    tCon.SubmitChanges();