画圆角用这个:
Public Declare Function CreateEllipticRgn Lib "gdi32" Alias "CreateEllipticRgn" (ByVal X1 As Long, ByVal Y1 As Long, ByVal X2 As Long, ByVal Y2 As Long) As Long
'功能:建立一个圆形或椭圆形的区域
'X1,Y1,X2,Y2分别为圆形/椭圆形外切矩形左上和右下角的x,y坐标
Public Declare Function SetWindowRgn Lib "user32" Alias "SetWindowRgn" (ByVal hWnd As Long, ByVal hRgn As Long, ByVal bRedraw As Boolean) As Long
'功能:设置窗口的工作区,它决定了所画窗口的范围,系统只显示该范围内的部分
'hWnd:要设置工作区的窗口句柄
'hRgn:区域句柄
'bRedraw:指示系统在设置工作区后是否重画窗口