消息映射的若干方法

Windows是个基于消息映射的系统，写程序当然就得处理处理了，消息映射还有一个好处是，消息队列不用维护，Windows自己管了，呵呵，省事啊～～～

1.比较快的方法是重载TApplication的OnMessage方法

例：void __fastcall TForm1::MyOnMessage(tagMSG &Msg, bool &Handled)
{
       TMessage Message;
       switch (Msg.message)
      {
              case WM_KEYDOWN:
                     Message.Msg = Msg.message;
                     Message.WParam = Msg.wParam;
                     Message.LParam = Msg.lParam;
                    MessageDlg("你按了一个键啊!", mtWarning, TMsgDlgButtons() << mbOK, 0);
                    Handled = true;
                    break;
        }
}
void __fastcall TForm1::FormCreate(TObject *Sender)
{
               Application->OnMessage = MyOnMessage;
} 

2.在.h中添加：

public：

void COPYDATA(TMessage & msg);

protected:
        BEGIN_MESSAGE_MAP
                VCL_MESSAGE_HANDLER(WM_COPYDATA, TMessage, COPYDATA)
        END_MESSAGE_MAP(TForm)

在.CPP中：

void TFormS::COPYDATA(TMessage &msg)
{
        if(msg.Msg==WM_COPYDATA)
        {
                COPYDATASTRUCT *pCDS = (COPYDATASTRUCT *)msg.LParam; //得到命令的详细内容
                int msgcmd=pCDS->dwData;//得到命令的类型
                int msglen=pCDS->cbData;//得到命令的长度；
                if(msglen>0)
                {
                        char *data=new char[msglen];
                        memcpy(data,pCDS->lpData,msglen);//命令的详细内容

                         处理data吧

                ｝

       ｝

｝

自己发送消息时：

   int server_var_table::sendmsg2ui(String msgs,int msgcmd)//发送消息到主窗口，通知主窗口修改控件
{
        HWND h=FormS->Handle;
        int msglen=msgs.Length()+1;
        char *msg = new char[msglen];
        memcpy(msg,msgs.c_str(),msglen);

        COPYDATASTRUCT cs;
        cs.dwData = msgcmd; //表示通知消息的类型
        cs.cbData = msglen;
        cs.lpData = msg;
        int x= SendMessage(h,WM_COPYDATA,(WPARAM)h,(LPARAM)(&cs));
        delete []msg;
        return x;
}

呵呵，搞定，收工先。