C # intercept the screen ↑
Today, I bored the code, turn out a function of a previous written C # screen capture ... I will share it with you. This code is rewritten with the C code of the online screen capture. Only declare the API. Each API is also attached. For reference. If you have any questions, please point out. (AppleDotNet@hotmail.com)
///
/// Intercept some screen ///
///
Upper left corner
///
Lower right corner
///
Whether is full screen
///
Return Value Bitmap
Public Static Bitmap GetPartScreen (Point P1, Point P2, Bool Full)
{
INTPTR HSCRDC, HMEMDC;
INTPTR HBITMAP, HOLDBITMAP;
INT NX, NY, NX2, NY2;
Nx = ny = nx2 = NY2 = 0;
INT NWIDTH, NHEIGHT;
Int xscrn, yscrn;
HSCRDC = CREATEDC ("Display", NULL, NULL, 0); // Create a DC handle
HMEMDC = CREATECOMPATIPLEDC (HSCRDC); // Create a memory DC
Xscrn = getDeviceCaps (HSCRDC, GetDeviceCapsindex.horzres); // Get screen width
YSCRN = getDeviceCaps (HSCRDC, getDeviceCapsindex.vertres); // Get the screen height
IF (full) // If it is intercepted the entire screen
{
Nx = 0;
NY = 0;
NX2 = xscrn;
NY2 = YSCRN;
}
Else
{
Nx = p1.x;
NY = p1.y;
NX2 = p2.x;
NY2 = p2.y;
/ / Check the legitimacy of numerical
IF (NX <0) nx = 0;
IF (NY <0) ny = 0;
IF (Nx2> xscrn) nx2 = xscrn;
IF (NY2> YSCRN) NY2 = YSCRN;
}
NWIDTH = NX2 - NX; // The width of the intercept range
NHEIGHT = NY2 - NY; / / The height of the intercept range
hbitmap = createcompatiblebitmap (HSCRDC, NWIDTH, NHEIGHT); // Copy from memory DC to HBitmap handle
HoldbitMap = SELECTOBJECT (HMEMDC, HBitmap);
Bitblt (HMEMDC, 0, 0, NWIDTH, NHEIGHT, HSCRDC, NX, NY, (UINT32) 0XCC0020);
Hbitmap = selectObject (HMEMDC, Holdbitmap);
DeleteDC (HSCRDC); // Delete the used object
Deletedc (hmemdc); // Delete the used object
Return bitmap.fromhbitmap (hbitmap); // Return Bitmap from Hbitmap with BitMap.Fromhbitmap
}
The API used is declared:
[DllImport ( "gdi32.dll")] public static extern IntPtr CreateDC (string lpszDriver, // driver name string lpszDevice, // device name string lpszOutput, // not used; should be NULL Int64 lpInitData // optional printer data); [DllImport ( "gdi32.dll")] public static extern IntPtr CreateCompatibleDC (IntPtr hdc // handle to DC); [DllImport ( "gdi32.dll")] public static extern int GetDeviceCaps (IntPtr hdc, // handle to DC GetDeviceCapsIndex nIndex // index of capability); [DllImport ( "gdi32.dll")] public static extern IntPtr CreateCompatibleBitmap (IntPtr hdc, // handle to DC int nWidth, // width of bitmap, in pixels int nHeight // height of bitmap , in pixels;
[DLLIMPORT ("gdi32.dll")] public static extern INTPTR SELECTOBJECT (INTPTR HDC, // Handle to DC INTPTR HGDIOBJ / / HANDLE TO Object);
[DLLIMPORT ("GDI32.DLL")] Public Static Extern Int Bitblt (INTPTR HDCDEST, // Handle to Destination DC INT NXDEST, // X-Coord of Destination Upper-Left Corner Int Nydest, // Y-Coord of Destination Upper -left corner int nWidth, // width of destination rectangle int nHeight, // height of destination rectangle IntPtr hdcSrc, // handle to source DC int nXSrc, // x-coordinate of source upper-left corner int nYSrc, // y -Coordinate of Source Upper-Left Corner Uint32 DWrop // Raster Operation Code);
[DLLIMPORT ("gdi32.dll")] public static extern int deletedc (INTPTR HDC // Handle to DC);
Posted on July 05, 2004 3:01 PM