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Visual C++

ShowBitmapView.cpp：源码内容
							// ShowBitmapView.cpp : implementation of the CShowBitmapView class
//
#include "stdafx.h"
#include "ShowBitmap.h"
#include "ShowBitmapDoc.h"
#include "ShowBitmapView.h"
#ifdef _DEBUG
#define new DEBUG_NEW
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#endif
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView
IMPLEMENT_DYNCREATE(CShowBitmapView, CView)
BEGIN_MESSAGE_MAP(CShowBitmapView, CView)
	//{{AFX_MSG_MAP(CShowBitmapView)
	ON_COMMAND(ID_FILE_OPEN, OnFileOpen)
	//}}AFX_MSG_MAP
	// Standard printing commands
	ON_COMMAND(ID_FILE_PRINT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_DIRECT, CView::OnFilePrint)
	ON_COMMAND(ID_FILE_PRINT_PREVIEW, CView::OnFilePrintPreview)
END_MESSAGE_MAP()
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView construction/destruction
// CShowBitmapView 构造/析构
CShowBitmapView::CShowBitmapView()
{
	// TODO: add construction code here
	state=0;
}
CShowBitmapView::~CShowBitmapView()
{
	
}
BOOL CShowBitmapView::PreCreateWindow(CREATESTRUCT& cs)
{
	// TODO: Modify the Window class or styles here by modifying
	//  the CREATESTRUCT cs
	return CView::PreCreateWindow(cs);
}
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView drawing
void CShowBitmapView::OnDraw(CDC* pDC)
{
	CShowBitmapDoc* pDoc = GetDocument();
	ASSERT_VALID(pDoc);
	// TODO: add draw code for native data here
	   if (!pDoc)
        return;
    if (state==1)
     {
        if (0 == extname.Compare(_T("bmp")))
         {
             CDC dcImage;
            if (!dcImage.CreateCompatibleDC(pDC))
             {
                return;
             }
             BITMAP bm;
             m_bitmap.GetBitmap(&bm);
             dcImage.SelectObject(&m_bitmap);
             pDC->BitBlt(0,0,bm.bmWidth,bm.bmHeight,&dcImage,0,0,SRCCOPY);
         }
        else
         {
            if (0 == extname.Compare(_T("jpg")))
             {
                 ShowJpgGif(pDC,BmpName,1,1);
             }
         }
     }
}
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView printing
BOOL CShowBitmapView::OnPreparePrinting(CPrintInfo* pInfo)
{
	// default preparation
	return DoPreparePrinting(pInfo);
}
void CShowBitmapView::OnBeginPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add extra initialization before printing
}
void CShowBitmapView::OnEndPrinting(CDC* /*pDC*/, CPrintInfo* /*pInfo*/)
{
	// TODO: add cleanup after printing
}
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView diagnostics
#ifdef _DEBUG
void CShowBitmapView::AssertValid() const
{
	CView::AssertValid();
}
void CShowBitmapView::Dump(CDumpContext& dc) const
{
	CView::Dump(dc);
}
CShowBitmapDoc* CShowBitmapView::GetDocument() // non-debug version is inline
{
	ASSERT(m_pDocument->IsKindOf(RUNTIME_CLASS(CShowBitmapDoc)));
	return (CShowBitmapDoc*)m_pDocument;
}
#endif //_DEBUG
/////////////////////////////////////////////////////////////////////////////
// CShowBitmapView message handlers
BOOL CShowBitmapView::ShowJpgGif(CDC* pDC,CString strPath, int x, int y)
{
    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;
}
void CShowBitmapView::ShowBitmap(CString BmpName)
{
    if (state==0)
     {            
         HBITMAP hBitmap=(HBITMAP)LoadImage(NULL,BmpName,IMAGE_BITMAP,0,0,LR_CREATEDIBSECTION|LR_DEFAULTSIZE|LR_LOADFROMFILE);
         m_bitmap.Detach();
         m_bitmap.Attach(hBitmap);
         state=1;
         Invalidate();
     }
}
void CShowBitmapView::OnFileOpen() 
{
	// TODO: Add your command handler code here
    //CFileDialog dlg(TRUE,_T("BMP"),_T("*.BMP"),OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,_T("位图文件(*.BMP;*.jpg)|*.BMP;*.jpg|"));   //这行代码可以打开BMP格式的图片
     CFileDialog dlg(TRUE,NULL,NULL,OFN_HIDEREADONLY|OFN_OVERWRITEPROMPT,_T("位图文件(*.BMP)|*.BMP|jpg文件(*.jpg)|*.jpg||")); //这行代码可以打开BMP和JPG格式的图片
	//gif格式图片的打开在这就不列出来了，留给各位自己尝试吧，对于gif格式图片的显示图片函数和jpg格式图片是同一个函数。
     if (IDOK==dlg.DoModal())
     {
         state=0; 
         BmpName.Format(_T("%s"),dlg.GetPathName());
         extname = dlg.GetFileExt();             //返回选定文件的扩展文件名
         extname.MakeLower();
         if (0==extname.Compare(_T("bmp")))
         {
             ShowBitmap(BmpName);
         }
         else
         {
             state=1;
         }
        Invalidate();
     }
	
}

						