1:
private void button1_Click(object sender, EventArgs e)
{
Bitmap bit =new Bitmap (Screen.AllScreens[0].Bounds.Width ,Screen.AllScreens[0].Bounds.Height);
Graphics g1 = Graphics.FromImage(bit);
g1.CopyFromScreen(new Point(0, 0), new Point(0, 0), bit.Size);
this.BackgroundImage =(Image)bit;
}
2:
[DllImport("user32", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern IntPtr GetDC(IntPtr hWnd);
[DllImport("GDI32", CharSet = CharSet.Ansi, SetLastError = true, ExactSpelling = true)]
private static extern int BitBlt(IntPtr srchDC, int srcX, int srcY, int srcW, int srcH, IntPtr desthDC, int destX, int destY, int op);
[System.Runtime.InteropServices.DllImportAttribute("gdi32.dll")]
private static extern IntPtr CreateDC(
string lpszDriver, // 驅動名稱
string lpszDevice, // 設備名稱
string lpszOutput, // 無用,可以設定位"NULL"
IntPtr lpInitData // 任意的打印機數據
);
private void button1_Click(object sender, EventArgs e)
{
IntPtr dc1 = CreateDC("DISPLAY", null, null, (IntPtr)null);
//由一個指定設備的句柄創建一個新的Graphics對象
Graphics g1 = Graphics.FromHdc(dc1);
Image ScreenImage = new Bitmap(Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, g1);
//根據屏幕大小創建一個與之相同大小的Bitmap對象
Graphics g2 = Graphics.FromImage(ScreenImage);
IntPtr dc3 = g1.GetHdc(); //獲得屏幕的句柄
IntPtr dc2 = g2.GetHdc(); //獲得位圖的句柄
BitBlt(dc2, 0, 0, Screen.PrimaryScreen.Bounds.Width, Screen.PrimaryScreen.Bounds.Height, dc3, 0, 0, 0xcc0020);//把當前屏幕拷貝到位圖中
g1.ReleaseHdc(dc3);//釋放屏幕句柄
g2.ReleaseHdc(dc2);//釋放位圖句柄
this.BackgroundImage = ScreenImage;
}