//1.定义方法

 procedure WMNCPaint(var Msg : TWMNCPaint); message WM_NCPAINT;

 //2.实现方法

 procedure TForm1.WMNCPaint(var Msg: TWMNCPaint);

 var

 dc:hDc;

 Pen:hPen;

 OldPen:hPen;

 OldBrush:hBrush;

 begin

     inherited;

     //获取本窗口设备上下文

     dc:=GetWindowDC(Handle);

     msg.Result:=;

     //创建画笔，实线、宽度为l、红色

     Pen:=CreatePen(PS_SOLID,,RGB(,,));

     //将新创建的画笔选入窗体的设备上下文

     OldPen:=SelectObject(dc,Pen);

     //将系统库存的空画刷入窗体的设备上下文

     OldBrush:=SelectObject(dc,GetStockObject(NULL_BRUSH));

     //给窗体“镶边”

     Rectangle(dc,,,Form1.Width,Form1.Height);

     //恢复旧画笔和旧画刷

     SelectObject(dc,OldBrush);

     SelectObject(dc,oldPen);

     //删除新创建的画笔，释放系统资源

     DeleteObject(Pen);

     //释放设备上下文

     ReleaseDC(Handle,Canvas.Handle);

 end; 

 //3.DBGrid控件描边

 procedure TForm1.FormPaint(Sender: TObject);

 var

 Rct:   TRect;

 begin

 Rct:=Rect(Dbgrid1.Left-,Dbgrid1.Top-,Dbgrid1.Left+Dbgrid1.Width+,Dbgrid1.top+Dbgrid1.Height+);

 with   Form1.Canvas   do

 begin

    Pen.Color   :=   clRed;

    Pen.Width   :=   ;

    Brush.Style   :=   bsClear;

    Rectangle(Rct);

 end;

 end;