用Delphi画圆角Panel的方法：

procedure TForm1.Button5Click(Sender: TObject);
var fhr :Thandle;
begin
fhr:=CreateRoundRectRgn(0,0,panel1.width,panel1.height,4,4);
SetWindowRgn(panel1.handle,fhr,true);
end;

Panel的BevelInner 及 BevelOuter 最好设成 bvNone

http://blog.csdn.net/iseekcode/article/details/4687570