MFC截屏生成bmp格式图片

void ScreenToBmp(CWnd*m_hwnd)

{

CRect rc;

m_hwnd->GetClientRect(&rc);

CClientDC dc(m_hwnd); //m_hwnd 创建客户区绘制内存

int iBitPerPixel = dc.GetDeviceCaps(BITSPIXEL);//像素相连颜色位数  

int iWidth = rc.Width(); //宽

int iHeight = rc.Height(); //高 

CDC memDC; //绘图对象

memDC.CreateCompatibleDC(&dc);

CBitmap memBitmap, *oldBitmap;

memBitmap.CreateCompatibleBitmap(&dc, iWidth, iHeight);

oldBitmap = memDC.SelectObject(&memBitmap);

memDC.BitBlt(0, 0, iWidth, iHeight, &dc, 0, 0, SRCCOPY);

BITMAP bmp;

memBitmap.GetBitmap(&bmp);

CString str; //获取系统时间 

CTime tm;

tm = CTime::GetCurrentTime();

str = tm.Format(L"%Y-%m-%d-%H-%M-%S");

str = _T(".//ShotPic//") + str + _T(".bmp");

char *pChar;

pChar = CstringToChar(str, pChar);

CreateDirectoryA(".//ShotPic", NULL);

FILE *fp;

fopen_s(&fp, pChar, "wb"); //".//ShotPic//test2.bmp"

BITMAPINFOHEADER bih; //位图信息头 

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

bih.biBitCount = bmp.bmBitsPixel;

bih.biCompression = BI_RGB;//表示不压缩  

bih.biHeight = bmp.bmHeight;

bih.biPlanes = 1; //位平面数，必须为1  

bih.biSize = sizeof(BITMAPINFOHEADER);

bih.biSizeImage = bmp.bmWidthBytes * bmp.bmHeight;

bih.biWidth = bmp.bmWidth;

BITMAPFILEHEADER bfh; //位图文件头 

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

bfh.bfOffBits = sizeof(BITMAPFILEHEADER)+sizeof(BITMAPINFOHEADER);

bfh.bfSize = bfh.bfOffBits + bmp.bmWidthBytes * bmp.bmHeight;

bfh.bfType = (WORD)0x4d42;//必须表示"BM"  

fwrite(&bfh, 1, sizeof(BITMAPFILEHEADER), fp);

fwrite(&bih, 1, sizeof(bih), fp);

byte * p = new byte[bmp.bmWidthBytes * bmp.bmHeight];

GetDIBits(memDC.m_hDC, (HBITMAP)memBitmap.m_hObject, 0, iHeight, p, (LPBITMAPINFO)&bih, DIB_RGB_COLORS);

fwrite(p, 1, bmp.bmWidthBytes * bmp.bmHeight, fp);

delete[] p;

fclose(fp);

memDC.SelectObject(oldBitmap);

return;

}