如何在MFC窗口显示BMP和JPG图片

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//通过资源画图
  static   void   DrawBitmap(UINT   bitmap,CDC   *pDC,CRect   rect)
  {
      CBitmap   bmp;
      if   (bmp.LoadBitmap(bitmap))
      {
      BITMAP   bmpInfo;
              bmp.GetBitmap(&bmpInfo);
              CDC   dcMemory;
              dcMemory.CreateCompatibleDC(pDC);
              dcMemory.SelectObject(&bmp);
      pDC->SetStretchBltMode(HALFTONE);
      pDC->StretchBlt(rect.left,rect.top,rect.Width(),rect.Height(),&dcMemory,0,0,bmpInfo.bmWidth,bmpInfo.bmHeight,SRCCOPY);
      }
  }

  //通过BMP文件画图
  static   void   drawBitmapFormFile(CString   BitmapFilePath,CDC   *pDC,CRect   rect)
  {
  HANDLE   filehandle=::LoadImage(NULL,BitmapFilePath,IMAGE_BITMAP,0,0,LR_LOADFROMFILE);
  if(filehandle!=NULL)
  {
  CBitmap   bmp;
  if(bmp.Attach(filehandle))
  {
                            BITMAP   bmpInfo;
                            bmp.GetBitmap(&bmpInfo);
                            CDC   dcMemory;
                            dcMemory.CreateCompatibleDC(pDC);
                            dcMemory.SelectObject(&bmp);
                            pDC->SetStretchBltMode(HALFTONE);
                            pDC->StretchBlt(rect.left,rect.top,rect.Width(),rect.Height(),&dcMemory,0,0,bmpInfo.bmWidth,bmpInfo.bmHeight,SRCCOPY);
    bmp.Detach();
  }
  }
  }

BOOL CShowBitmapView::ShowJpgGif(CDC* pDC,CString strPath, int x, int y)//读取文件信息方式打开JPG等图片文件
{
    IStream *pStm;
    CFileStatus fstatus;
    CFile file;
    LONG cb;
    //打开文件并检测文件的有效性
    if (file.Open(strPath,CFile::modeRead)&&
        file.GetStatus(strPath,fstatus)&&
        ((cb = fstatus.m_size) != -1))
    {
        HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, cb);
        LPVOID pvData = NULL;
        if (hGlobal != NULL)
        {
            pvData = GlobalLock(hGlobal);
            if (pvData != NULL)
            {
                //file.ReadHuge(pvData, cb);  //6.0中可能是用这个函数
                file.Read(pvData, cb);  //VC2005.NET中用这个函数
                GlobalUnlock(hGlobal);
                CreateStreamOnHGlobal(hGlobal, TRUE, &pStm);
            }
        }
    }
    else
    {
        return false;
    } //打开文件结束
    //显示JPEG和GIF格式的图片，GIF只能显示一帧，还不能显示动画，
    //要显示动画GIF请使用ACTIVE控件。
    IPicture *pPic;
    //load image from file stream
    if(SUCCEEDED(OleLoadPicture(pStm,fstatus.m_size,TRUE,IID_IPicture,(LPVOID*)&pPic)))
    {
        OLE_XSIZE_HIMETRIC hmWidth;
        OLE_YSIZE_HIMETRIC hmHeight;
        pPic->get_Width(&hmWidth);
        pPic->get_Height(&hmHeight);
        double fX,fY;
        //get image height and width
        fX = (double)pDC->GetDeviceCaps(HORZRES)*(double)hmWidth/((double)pDC->GetDeviceCaps(HORZSIZE)*100.0);
        fY = (double)pDC->GetDeviceCaps(VERTRES)*(double)hmHeight/((double)pDC->GetDeviceCaps(VERTSIZE)*100.0);
        //use render function display image
        if(FAILED(pPic->Render(*pDC,x,y,(DWORD)fX,(DWORD)fY,0,hmHeight,hmWidth,-hmHeight,NULL)))
        {
            pPic->Release();
            return false;
        }
        pPic->Release();
    }
    else
    {
        return false;
    }
    return true;
}