C#利用Windows自带gdi32.dll实现抓取屏幕功能实例

internal static void GetScreenShot( ){  //获得当前屏幕的大小   Rectangle rect = new Rectangle();  rect = Screen.AllScreens[0].WorkingArea;     //计算图片的大小，因为图片的长和宽有可能超过目前屏幕的大小   //创建一个以当前屏幕为模板的图象   Control ctl = new Control();  Graphics g1 = ctl.CreateGraphics();  //创建以屏幕大小为标准的位图   Image MyImage = new Bitmap(rect.Width ,rect .Height, g1);  Graphics g2 = Graphics.FromImage(MyImage);  //得到屏幕的DC   IntPtr dc1 = g1.GetHdc();  //得到Bitmap的DC   IntPtr dc2 = g2.GetHdc();  //调用此API函数，实现屏幕捕获   BitBlt(dc2, 0, 0, rect.Width, rect.Height, dc1, 0, 0, 13369376);  //释放掉屏幕的DC   g1.ReleaseHdc(dc1);  //释放掉Bitmap的DC   g2.ReleaseHdc(dc2);  //以JPG文件格式来保存   //Image.GetThumbnailImageAbort myCallback = new Image.GetThumbnailImageAbort(ThumbnailCallback);  //return MyImage.GetThumbnailImage(control.Width, control.Height, myCallback, IntPtr.Zero);  MyImage.Save("D://aa.jpg"); }[System.Runtime.InteropServices.DllImportAttribute("gdi32.dll")]private static extern bool BitBlt( IntPtr hdcDest,  //目标设备的句柄 int nXDest,    //目标对象的左上角的X坐标 int nYDest,    //目标对象的左上角的X坐标 int nWidth,    //目标对象的矩形的宽度 int nHeight,    //目标对象的矩形的长度 IntPtr hdcSrc,   //源设备的句柄 int nXSrc,     //源对象的左上角的X坐标 int nYSrc,     //源对象的左上角的X坐标 System.Int32 dwRop //光栅的操作值);