使用VC实现JPG图片加载


在OnDraw（）函数中添加如下的代码，并在工程目录下放入test.jpg的图片。 
IPicture *pPic; 
IStream *pStm; 
CFileStatus fstatus; 
CFile file; 
LONG cb; 
if (file.Open("test.jpg",CFile::modeRead)&&file.GetStatus("test.jpg", fstatus)&& ((cb = fstatus.m_size) != -1)) 
{ 
HGLOBAL hGlobal = GlobalAlloc(GMEM_MOVEABLE, cb); 
LPVOID pvData = NULL; 
if (hGlobal != NULL) 
{ 
if ((pvData = GlobalLock(hGlobal)) != NULL) 
{ 
file.ReadHuge(pvData, cb); 
GlobalUnlock(hGlobal); 
CreateStreamOnHGlobal(hGlobal, TRUE, &pStm); 
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; 
CRect rect; 
GetClientRect(rect); 
fX=rect.Width(); 
fY=rect.Height(); 
//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); 
if(FAILED(pPic->Render(*pDC,0,0,(DWORD)fX,(DWORD)fY,0,hmHeight,hmWidth,-hmHeight,NULL))) AfxMessageBox("Failed To Render The picture!"); 
pPic->Release(); 
} 
else 
AfxMessageBox("Error Loading Picture From Stream!"); 
} 
} 
} 
else 
AfxMessageBox("Cant Open Image File!");

补充：软件开发 , Vc ,