全屏截取?

 全屏截取(改)  
    潘小龙,顾时明二人著的”用VC进行屏幕截取编程 “一文中的代码有多处错误，我在yu_hl大虾的大力协助下对其进行修正，以下代码只需复制粘帖就能使用:
    文件保存在C盘根目录.

    CString dt;
    CTime m_CurDT;
    m_CurDT=CTime::GetCurrentTime();
    dt.Format(“%d-%d-%d “,m_CurDT.GetYear(),m_CurDT.GetMonth(),m_CurDT.GetDay());
    dt+=m_CurDT.Format(“%H时%M分%S秒”);
    dt+=”.bmp”;
    CString bmpname;
    bmpname=”c:\\”;    
    bmpname+=dt;       

    HDC       hScrDC, hMemDC;      
    // 屏幕和内存设备描述表
    int       nX, nY, nX2, nY2;          
    // 位图宽度和高度
    int       xScrn, yScrn;        
    // 屏幕分辨率
    HBITMAP    hBitm ap, hOldBitmap;  

    //为屏幕创建设备描述表
    hScrDC = CreateDC(“DISPLAY”, NULL, NULL, NULL);
    //为屏幕设备描述表创建兼容的内存设备描述表
    hMemDC = CreateCompatibleDC(hScrDC);
    // 获得屏幕分辨率
    xScrn = GetDeviceCaps(hScrDC, HORZRES);
    yScrn = GetDeviceCaps(hScrDC, VERTRES);
    // 获得全屏坐标
    nX = 0;
    nY = 0;
    nX2 = xScrn;
    nY2 = yScrn;
  
    // 创建一个与屏幕设备描述表兼容的位图
    hBitmap = CreateCompatibleBitmap(hScrDC, nX2, nY2);
    // 把新位图选到内存设备描述表中
    hOldBitmap = (HBITMAP)SelectObject(hMemDC, hBitmap);
    // 把屏幕设备描述表拷贝到内存设备描述表中
    BitBlt(hMemDC, 0, 0, nX2, nY2, hScrDC, nX, nY, SRCCOPY);
    //得到屏幕位图的句柄
    hBitmap = (HBITMAP)SelectObject(hMemDC, hOldBitmap);
    //清除
    DeleteDC(hScrDC);
    DeleteDC(hMemDC);

    HDC            hDC;        
    int            iBits;      
    //当前显示分辨率下每个像素所占字节数
    WORD           wBitCount;  
       //位图中每个像素所占字节数
    //定义调色板大小， 位图中像素字节大小 ，
    DWORD          dwPaletteSize=0,
                    dwBmBitsSize,
                    dwDIBSize, dwWritten;
    BITMAP          Bitmap;        
    //位图属性结构
    BITMAPFILEHEADER   bmfHdr;        
    //位图文件头结构
    BITMAPINFOHEADER   bi;            
    //位图信息头结构
    LPBITMAPINFOHEADER lpbi;          
    //指向位图信息头结构
    HANDLE           fh, hDib, hPal,hOldPal=NULL;
    //定义文件，分配内存句柄，调色板句柄
  
    //计算位图文件每个像素所占字节数
    hDC = CreateDC(“DISPLAY”,NULL,NULL,NULL);
    iBits = GetDeviceCaps(hDC, BITSPIXEL) *
    GetDeviceCaps(hDC, PLANES);
    DeleteDC(hDC);
    if (iBits <= 1)
      wBitCount = 1;
    else if (iBits <= 4)
      wBitCount = 4;
    else if (iBits <=
      wBitCount = 8;
    else if (iBits <= 24)
      wBitCount = 24;
    else
    wBitCount = iBits;
    //计算调色板大小
    if (wBitCount <=
      dwPaletteSize = (1 <<  wBitCount) *
      sizeof(RGBQUAD);
  
    //设置位图信息头结构
    GetObject(hBitmap, sizeof(BITMAP), (LPSTR)&Bitmap);
    bi.biSize            = sizeof(BITMAPINFOHEADER);
    bi.biWidth           = Bitmap.bmWidth;
    bi.biHeight          = Bitmap.bmHeight;
    bi.biPlanes          = 1;
    bi.biBitCount        = wBitCount;
    bi.biCompression     = BI_RGB;
    bi.biSizeImage       = 0;
    bi.biXPelsPerMeter   = 0;
    bi.biYPelsPerMeter   = 0;
    bi.biClrUsed          = 0;
    bi.biClrImportant    = 0;

    dwBmBitsSize = ((Bitmap.bmWidth * wBitCount+31)/32) * 4 * Bitmap.bmHeight;
    //为位图内容分配内存
    hDib  = GlobalAlloc(GHND,dwBmBitsSize+dwPaletteSize+sizeof(BITMAPINF OHEADER));
    lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);
    *lpbi = bi;

    // 处理调色板  
    hPal = GetStockObject(DEFAULT_PALETTE);
    if (hPal)
    {
      hDC = ::GetDC(NULL);
      hOldPal = SelectPalette(hDC,(HPALETTE)hPal, FALSE);
      RealizePalette(hDC);
    }
    // 获取该调色板下新的像素值
    GetDIBits(hDC, hBitmap, 0, (UINT) Bitmap.bmHeight,(LPSTR)lpbi + sizeof(BITMAPINFOHEADER)+dwPaletteSize,(BITMAPINFO*)lpbi,DIB _RGB_COLORS);
    //恢复调色板  
    if (hOldPal)
    {
      SelectPalette(hDC, (HPALETTE)hOldPal, TRUE);
      RealizePalette(hDC);
      ::ReleaseDC(NULL, hDC);
    }

     //创建位图文件    
     fh = CreateFile(bmpname, GENERIC_WRITE, 0, NULL, CREATE_ALWAYS,FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL);
     // 设置位图文件头
     bmfHdr.bfType = 0x4D42;  // “BM”
     dwDIBSize = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER) + dwPaletteSize + dwBmBitsSize;  
     bmfHdr.bfSize = dwDIBSize;
     bmfHdr.bfReserved1 = 0;
     bmfHdr.bfReserved2 = 0;
     bmfHdr.bfOffBits = (DWORD)sizeof
     (BITMAPFILEHEADER) + (DWORD)sizeof(BITMAPINFOHEADER) + dwPaletteSize;
     // 写入位图文件头
     WriteFile(fh, (LPSTR)&bmfHdr, sizeof(BITMAPFILEHEADER), &dwWritten, NULL);
     // 写入位图文件其余内容
     WriteFile(fh, (LPSTR)lpbi, dwDIBSize,
     &dwWritten, NULL);
     //清除  
     GlobalUnlock(hDib);
     GlobalFree(hDib);
     CloseHandle(fh);