參考：http://bbs.csdn.net/topics/330154355

#include "stdio.h"

#include "windows.h"

/************************************************************************/

/* hBitmap    为刚才的屏幕位图句柄

/* lpFileName 为须要保存的位图文件名称

/************************************************************************/

int SaveBitmapToFile(HBITMAP hBitmap,LPSTR lpFileName)

{

    HDC            hDC; //设备描写叙述表

    int            iBits;//当前显示分辨率下每一个像素所占字节数

    WORD           wBitCount;//位图中每一个像素所占字节数

    DWORD          dwPaletteSize=0;//定义调色板大小

    DWORD          dwBmBitsSize;//位图中像素字节大小

    DWORD          dwDIBSize;// 位图文件大小

    DWORD          dwWritten;//写入文件字节数

    BITMAP         Bitmap;//位图结构

    BITMAPFILEHEADER   bmfHdr;   //位图属性结构

    BITMAPINFOHEADER   bi;       //位图文件头结构

    LPBITMAPINFOHEADER lpbi;     //位图信息头结构     指向位图信息头结构

    HANDLE          fh;//定义文件句柄

    HANDLE            hDib;//分配内存句柄

    HANDLE            hPal;//分配内存句柄

    HANDLE          hOldPal=NULL;//调色板句柄  

    //计算位图文件每一个像素所占字节数

    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 <= 8)

        wBitCount = 8;

    else if (iBits <= 24)

        wBitCount = 24;

    else if (iBits<=32)

        wBitCount = 24;

    //计算调色板大小

    if (wBitCount <= 8)

        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(BITMAPINFOHEADER));

    lpbi = (LPBITMAPINFOHEADER)GlobalLock(hDib);

    if (lpbi==NULL)

    {

        return 0;

    }

    *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,

        (LPBITMAPINFO)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(lpFileName, GENERIC_WRITE,

        0, NULL, CREATE_ALWAYS,

        FILE_ATTRIBUTE_NORMAL | FILE_FLAG_SEQUENTIAL_SCAN, NULL);   

    if (fh == INVALID_HANDLE_VALUE)

        return FALSE;

    // 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);

    return 1;

}

HBITMAP   GetCaptureBmp()

{

    HDC     hDC;

    HDC     MemDC;

    BYTE*   Data;

    HBITMAP   hBmp;

    BITMAPINFO   bi;   

    memset(&bi,   0,   sizeof(bi));

    bi.bmiHeader.biSize   =   sizeof(BITMAPINFO);

    bi.bmiHeader.biWidth   =  GetSystemMetrics(SM_CXSCREEN);

    bi.bmiHeader.biHeight   = GetSystemMetrics(SM_CYSCREEN);

    bi.bmiHeader.biPlanes   =   1;

    bi.bmiHeader.biBitCount   =   24;   

    hDC   =   GetDC(NULL);

    MemDC   =   CreateCompatibleDC(hDC);

    hBmp   =   CreateDIBSection(MemDC,   &bi, DIB_RGB_COLORS,   (void**)&Data,   NULL,   0);

    SelectObject(MemDC,   hBmp);

    BitBlt(MemDC,   0,   0,   bi.bmiHeader.biWidth,   bi.bmiHeader.biHeight,hDC,   0,   0,   SRCCOPY);

    ReleaseDC(NULL,   hDC);

    DeleteDC(MemDC);

    return   hBmp;

}   

void main()

{

    HBITMAP   hBmp;

    hBmp   =   GetCaptureBmp();

    SaveBitmapToFile(hBmp,"c:\\11.bmp");

}