namespace WindowsFormsApplication1
{
public partial class Form1 : Form
{
public Form1()
{
InitializeComponent();
}
private void Form1_Paint(object sender, PaintEventArgs e)
{
}
public Bitmap GetDesktopImage()
{
SIZE size;
IntPtr hBitmap;
IntPtr hDC = PlatformInvokeUSER32.GetDC(listBox1.Handle);
IntPtr hMemDC = PlatformInvokeGDI32.CreateCompatibleDC(hDC);
size.cx = listBox1.Width;
size.cy = listBox1.Height;
hBitmap = PlatformInvokeGDI32.CreateCompatibleBitmap(hDC, size.cx, size.cy);
if (hBitmap != IntPtr.Zero)
{
IntPtr hOld = (IntPtr)PlatformInvokeGDI32.SelectObject(hMemDC, hBitmap);
PlatformInvokeGDI32.BitBlt(hMemDC, 0, 0, size.cx, size.cy, hDC, 0, 0, PlatformInvokeGDI32.SRCCOPY);
PlatformInvokeGDI32.SelectObject(hMemDC, hOld);
PlatformInvokeGDI32.DeleteDC(hMemDC);
PlatformInvokeUSER32.ReleaseDC(listBox1.Handle, hDC);
Bitmap bmp = System.Drawing.Image.FromHbitmap(hBitmap);
PlatformInvokeGDI32.DeleteObject(hBitmap);
GC.Collect();
return bmp;
}
return null;
}
private void button1_Click(object sender, EventArgs e)
{
pictureBox1.Image = GetDesktopImage();
}
}
[StructLayout(LayoutKind.Sequential)]
public struct SIZE
{
public int cx;
public int cy;
}
public class PlatformInvokeGDI32
{
public const int SRCCOPY = 13369376;
[DllImport("gdi32.dll", EntryPoint = "DeleteDC")]
public static extern IntPtr DeleteDC(IntPtr hDC);
[DllImport("gdi32.dll", EntryPoint = "DeleteObject")]
public static extern IntPtr DeleteObject(IntPtr hDC);
[DllImport("gdi32.dll", EntryPoint = "BitBlt")]
public static extern bool BitBlt(IntPtr hdcDest, int xDest, int yDest, int wDest, int hDest, IntPtr hdcSource, int xSrc, int ySrc, int rasterOp);
[DllImport("gdi32.dll", EntryPoint = "CreateCompatibleBitmap")]
public static extern IntPtr CreateCompatibleBitmap(IntPtr hDC,int nWidth,int hHeight);
[DllImport("gdi32.dll", EntryPoint = "CreateCompatibleDC")]
public static extern IntPtr CreateCompatibleDC(IntPtr hDC);
[DllImport("gdi32.dll", EntryPoint = "SelectObject")]
public static extern IntPtr SelectObject(IntPtr hDC,IntPtr bmp);
}
public class PlatformInvokeUSER32
{
public const int SM_CXSCREEN = 0;
public const int SM_CYSCREEN = 1;
[DllImport("user32.dll", EntryPoint = "GetDesktopWindow")]
public static extern IntPtr GetDesktopWindow();
[DllImport("user32.dll", EntryPoint = "GetDC")]
public static extern IntPtr GetDC(IntPtr ptr);
[DllImport("user32.dll", EntryPoint = "GetSystemMetrics")]
public static extern int GetSystemMetrics(int abc);
[DllImport("user32.dll", EntryPoint = "GetWindowDC")]
public static extern IntPtr GetWindowDC(Int32 ptr);
[DllImport("user32.dll", EntryPoint = "ReleaseDC")]
public static extern IntPtr ReleaseDC(IntPtr hWnd, IntPtr hDc);
}
} |
