在加入期间LINQ在线属性更新

为您的ClassA添加更新方法

class ClassA {
  public ClassA UpdateWithB(ClassB objectB) {
    // Do the update
    return this;
  }
}

然后用

return from objectA in GetObjectAs()
   join objectB in GetObjectBs()
           on objectA.Id equals objectB.AId
           // update object A with object B data before selecting it
   select objectA.UpdateWithB(objectB);

编辑:

或使用本地lambda函数,如:

Func f = ((a,b)=> { a.DoSomethingWithB(b); return a;});
return from objectA in GetObjectAs()
       join objectB in GetObjectBs()
       on objectA.Id equals objectB.AId
       select f(objectA , objectA );