C#取得当前窗体图片

   Yesterday,客户对需求提出了一些变更,其中有提到一点就是要打印当前的确窗体.
想到的一个解决方案就是模拟按下ALT+PRNT的组合键,然后从CLIPBOARD中取的要打印的图形.
当然,第一步是要取得你当前的窗体..实现方法如下:
  [DllImport("user32.dll")]
  private static extern IntPtr GetDC(IntPtr hwnd);
  [DllImport("user32.dll")]
  private static extern IntPtr ReleaseDC(IntPtr hc,IntPtr hDest);
   [DllImport("user32.dll")]
  private static extern IntPtr GetWindowDC(IntPtr hwnd);
  [DllImport("user32.dll")]
  private static extern IntPtr GetForegroundWindow();
  [DllImport("user32.dll")]
  private static extern int GetWindowRect(IntPtr hwnd,
   ref  RECT lpRect);
 private Bitmap GetActiveForm()
{
   IntPtr platDC = GetForegroundWindow();
   IntPtr  windDC = GetWindowDC(platDC);
   Rect rect = new Rect();
  GetWindowRect(windDC,ref  rect);
  Bitmap bmp = new Bitmap(rect.right - right.left,rect.bottom - rect.top);
Graphics g = Graphics.FromIamge(bmp);
 IntPtr hdc = g.getHdc();
BitBlt( hdc,0,0,bmp.width,bmp.height,windDC,0,0,3278651);
g.ReleaseHdc(hdc);
g.dispose();
ReleaseDC(platDC,winDC);
return bmp;
}

private void print()
{
   Bitmap bm = new Bitmap();
  bm = GetActiveForm();
// past the bmp to clipboard
  SendKeys.Send("%{PRTSC}");
  Application.DoEvents();

// print bmp
    IDataObject   iData   =   Clipboard.GetDataObject   ();  
   Image   img   =   (Image)iData.GetData   (DataFormats.Bitmap);  
   e.Graphics.DrawImage(img,0,0);  

}


That's all!!