vc 保存界面上控件为图片

void CDlgDlg::OnSave() 
{
// TODO: Add your control notification handler code here
CRect rect;
HBITMAP hBmp;

GetDlgItem(IDC_PIC)->GetWindowRect(rect);
ScreenToClient(rect);

CString strFilter="Bitmap Files (*.bmp)|*.bmp||";
CFileDialog dlg(FALSE,"bmp", NULL, OFN_HIDEREADONLY|OFN_EXPLORER, strFilter, NULL); 
if (dlg.DoModal() == IDOK) 
{
   hBmp=GetSrcBit(rect);
   SaveBmp(hBmp,dlg.GetPathName());
}
}

HBITMAP CDlgDlg::GetSrcBit(CRect rect) 
{ 
HDC hBufDC,hDC; 
HBITMAP hBitmap, hBitTemp;

CClientDC dc(this);
hDC=dc.GetSafeHdc();
//创建设备上下文(HDC) 
hBufDC = CreateCompatibleDC(NULL); 

//创建HBITMAP 
hBitmap = CreateCompatibleBitmap(hDC,rect.Width(),rect.Height()); 
hBitTemp = (HBITMAP) SelectObject(hBufDC, hBitmap); 

//得到位图缓冲区 
StretchBlt(hBufDC,0,0,rect.Width(),rect.Height(), 
   hDC,rect.left,rect.top,rect.Width(),rect.Height(),SRCCOPY); 

//得到最终的位图信息 
hBitmap = (HBITMAP) SelectObject(hBufDC, hBitTemp); 

//释放内存 

DeleteObject(hBitTemp); 
::DeleteDC(hBufDC); 
ReleaseDC(&dc);
return hBitmap; 
}

BOOL CDlgDlg::SaveBmp(HBITMAP hBitmap, CString FileName) 
{ 
//设备描述表 
HDC hDC; 
//当前分辨率下每象素所占字节数 
int iBits; 
//位图中每象素所占字节数 
WORD wBitCount; 
//定义调色板大小， 位图中像素字节大小 ，位图文件大小 ， 写入文件字节数 
DWORD dwPaletteSize=0, dwBmBitsSize=0, dwDIBSize=0, dwWritten=0; 
//位图属性结构 
BITMAP Bitmap; 
//位图文件头结构 
BITMAPFILEHEADER bmfHdr; 
//位图信息头结构 
BITMAPINFOHEADER bi; 
//指向位图信息头结构 
LPBITMAPINFOHEADER lpbi; 
//定义文件，分配内存句柄，调色板句柄 
HANDLE fh,hDib,hOldPal=NULL; 
//HANDLE hPal;
//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 <= 8) wBitCount = 8; 
else wBitCount = 24; 

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.biClrImportant = 0; 
bi.biClrUsed = 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); 
*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(FileName, 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 TRUE; 
}