C# 如何在Event中收到消息，通知给窗体，或者另一个Thread

Question

用事件//窗体A
FormB b =new FormB();
b.ReceiveData += ReceiveData;
private void ReceiveData(string card)
{
   MessageBox.Show(card);
}//窗体B
public  void delegate ReceiveDataHandler(string card);
public ReceiveDataHandler ReceiveData; private void OnCardReadEvent(string card)
 {
           MessageBox.Show(card, "Message");
　　　//这边要怎么实现，通知窗体或者另一个Thread
            if(ReceiveData!=null)
            {
                    ReceiveData(card);
            }
}

Answer 1

http://blog.163.com/liujiyun123@126/blog/static/4459677620108295850128/

Answer 2

知道原因了，是DLL里的事件是要Open　RS232后，才Start Thread, 有数据才用Event通知谢谢！