vc显示jpg,gif图像简单方法

VC没有直接显示JPG图片的方法，在网上找了个比较简单的列子自己改了下，还挺好用，下面一个函数就行了

[cpp]
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ShowJpgGif(CDC* pDC,CString strPath, int x, int y)  
{  
      IStream *pStm;   
      CFileStatus fstatus;   
      CFile file;   
      LONG cb;   
      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.Read(pvData, cb);   
                        GlobalUnlock(hGlobal);   
                        CreateStreamOnHGlobal(hGlobal, TRUE, &pStm);   
                  }  
            }  
      }  
      else  
            return false;  
      //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;  
}  

ShowJpgGif(CDC* pDC,CString strPath, int x, int y)
{
IStream *pStm;
CFileStatus fstatus;
CFile file;
LONG cb;
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.Read(pvData, cb);
GlobalUnlock(hGlobal);
CreateStreamOnHGlobal(hGlobal, TRUE, &pStm);
}
}
}
else
return false;
//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;
}

使用方法：

在对话框上放一个cstatic控件IDC_STC_DUMMY，调整控件大小使得图片能够完全显示

[cpp]
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CDC* pDC = GetDlgItem(IDC_STC_DUMMY)->GetDC();