重载CreateParams实现无标题栏的窗体

重载TForm类的CreateParams(TCreateParams& Params)方法。

void __fastcall CreateParams(TCreateParams& Params)
{
  Params.Style&=WS_CAPTION;
  TForm::CreateParams(Params);
}

截取Windows的WM_NCHITTEST消息
在头文件中加入
private:
        void __fastcall WMNChitTest(TMessage& Msg);
protected:
        BEGIN_MESSAGE_MAP
          VCL_MESSAGE_HANDLER(WM_NCHITTEST,TMessage,WMNChitTest)
        END_MESSAGE_MAP(TForm)

在主文件中加入
void __fastcall WMNChitTest(TMessage& Msg)
{
  if(GetAsyncKeyState(VK_LBUTTON)<0)
    Msg.Result=HTCAPTION;
  else
    Msg.Result=HTCLIENT;
}