在屏幕上画图的C＃实现代码

DllImport所在的名字空间 using System.Runtime.InteropServices; [DllImport( " User32.dll " )] public extern static System.IntPtr GetDC(System.IntPtr hWnd); private void button19_Click( object sender, EventArgs e) { System.IntPtr DesktopHandle = GetDC(System.IntPtr.Zero); Graphics g = Graphics.FromHdc(DesktopHandle); g.DrawRectangle( new Pen(Color.Red), new Rectangle( 10 , 10 , 100 , 100 )); }