VC:添加图片

      总体：对于普通的BMP\DIB格式的图片，GDI中提供了LoadImage()函数；对于PNP、JPG、GIF、等格式的文件VC++中提供了OleLoadPicture()函数。

一、

1、创建一个单文档应用程序，并在View类中添加函数、变量如下：

       void LoadPicture();

       LPPICTURE m_picture;

       float size;

       CString filename;

2、LoadPicture();函数代码如下：

void CTestView::LoadPicture()

//LPPICTRUE LoadPicture(CStirng filename)

{

       HANDLE hfile=CreateFile(filename,GENERIC_READ,0,NULL,OPEN_EXISTING,0,NULL);

       _ASSERTE(INVALID_HANDLE_VALUE!=hfile);

       DWORD dfilesize=GetFileSize(hfile,NULL);

       _ASSERTE(-1!=dfilesize);

       LPVOID p=NULL;

       HGLOBAL h=GlobalAlloc(GMEM_MOVEABLE,dfilesize);

       _ASSERTE(NULL!=h);

       p=GlobalLock(h);

       _ASSERTE(NULL!=p);

       DWORD dw=0;

       BOOL bread=ReadFile(hfile,p,dfilesize,&dw,NULL);

       _ASSERTE(FALSE!=bread);

       GlobalUnlock(h);

       CloseHandle(hfile);

       LPSTREAM pstm=NULL;

       HRESULT hr=CreateStreamOnHGlobal(h,TRUE,&pstm);

       _ASSERTE(SUCCEEDED(hr)&&pstm);

       if(m_picture)

              m_picture->Release();

       hr=::OleLoadPicture(pstm,dfilesize,FALSE,IID_IPicture,(LPVOID *)&m_picture);

       _ASSERTE(SUCCEEDED(hr)&&m_picture);

       pstm->Release();

//return m_picture;

}

3、在工具栏中添加两个按钮，扩大、缩小。在View类中，添加文件打开：

void CTestView::OnFileOpen()

{

       // TODO: Add your command handler code here

       static char sfile[]="JPEG(*.JPEG;*.JPE;*.JIF;*.JPG)|*.JPEG;*.JPE;*.JIF;*.JPG|BMP Windows位图(*.BMP;*.DIB;*.RLE)|*.BMP;*.DIB;*.RLE|PNG(*.PNG)|*.PNG||";

       CFileDialog dlg(TRUE,"jpg"," ",OFN_ALLOWMULTISELECT,sfile);

       if(IDOK==dlg.DoModal())

       {

              filename=dlg.GetPathName();

              LoadPicture();

       }

       Invalidate();   

}

void CTestView::OnBig()

{

       // TODO: Add your command handler code here

       size=size*0.909;

       Invalidate();

}

void CTestView::OnSmall()

{

       // TODO: Add your command handler code here

       size=size*1.1;

       Invalidate();

}

4、编写OnDraw函数代码：

void CTestView::OnDraw(CDC* pDC)

{

       CTestDoc* pDoc = GetDocument();

       ASSERT_VALID(pDoc);

       // TODO: add draw code for native data here

       if(m_picture)

       {

      

              long width;

              long height;

              m_picture->get_Width(&width);

              m_picture->get_Height(&height);

              int nwidth=MulDiv(width,GetDeviceCaps(pDC->GetSafeHdc(),LOGPIXELSX),

                     2540);

              int nheight=MulDiv(height,GetDeviceCaps(pDC->GetSafeHdc(),LOGPIXELSY),

                     2540);    

      

              CRect rc;

              GetClientRect(&rc);     

              m_picture->Render(pDC->GetSafeHdc(),(rc.Width()-nwidth/size)/2,(rc.Height()-nheight/size)/2,

                                  nwidth/size,nheight/size,0,height,width,-height,&rc);

       }

}

二、

1、添加位图资源

2、函数如下：

void CTestDlg::OnPaint()

{

       if (IsIconic())

       {

              CPaintDC dc(this); // device context for painting

              SendMessage(WM_ICONERASEBKGND, (WPARAM) dc.GetSafeHdc(), 0);

              // Center icon in client rectangle

              int cxIcon = GetSystemMetrics(SM_CXICON);

              int cyIcon = GetSystemMetrics(SM_CYICON);

              CRect rect;

              GetClientRect(&rect);

              int x = (rect.Width() - cxIcon + 1) / 2;

              int y = (rect.Height() - cyIcon + 1) / 2;

              // Draw the icon

              dc.DrawIcon(x, y, m_hIcon);

       }

       else

       {

              CPaintDC dc(this);

        CRect rect;

        GetClientRect(&rect);//得到窗体的大小

        CDC dcMem;

        dcMem.CreateCompatibleDC(&dc);

        CBitmap bmpBackground;

        bmpBackground.LoadBitmap(IDB_BITMAP1);//加载背景图片

        BITMAP bitMap;

        bmpBackground.GetBitmap(&bitMap);

        CBitmap *pbmpOld=dcMem.SelectObject(&bmpBackground);

        dc.StretchBlt(0,0,rect.Width(),rect.Height(),&dcMem,0,0,bitMap.bmWidth,bitMap.bmHeight,SRCCOPY);//画窗体

//            CDialog::OnPaint();

       }

}

三、

1、位图：

       CPaintDC dc(this);

        CRect rect;

        GetClientRect(&rect);//得到窗体的大小

        CDC dcMem;

        dcMem.CreateCompatibleDC(&dc);

        CBitmap bmpBackground;

        bmpBackground.LoadBitmap(IDB_BITMAP1);//加载背景图片

        BITMAP bitMap;

        bmpBackground.GetBitmap(&bitMap);

        CBitmap *pbmpOld=dcMem.SelectObject(&bmpBackground);

              long width;

                     width=bitmap.bmWidth;

                     //m_picture->get_Width(&width);

              long height;

                     height;=bitmap.bmHeight;

                     //m_picture->get_Height(&height);

              COLORREF color1,color2;

              for(long i=0;i<height/2;i++)

              {

                     for(long j=0;j<width;j++)

                     {

                            color1=dcMem.GetPixel(j,i);

                            color2=dcMem.GetPixel(width-j,height-i);

                            dcMem.SetPixel(j,i,color2);

                            dcMem.SetPixel(width-j,height-i,color1);

                     }    

              }*/

        dc.StretchBlt(0,0,rect.Width(),rect.Height(),&dcMem,0,0,bitMap.bmWidth,bitMap.bmHeight,SRCCOPY);//画窗体

2、图片：

       /*CPaintDC dc(this);

             CDC dcMem;

        dcMem.CreateCompatibleDC(&dc);

              long width;

                     m_picture->get_Width(&width);

              long height;

                     m_picture->get_Height(&height);

              COLORREF color1,color2;

              for(long i=0;i<height/2;i++)

              {

                     for(long j=0;j<width;j++)

                     {

                            color1=dcMem.GetPixel(j,i);

                            color2=dcMem.GetPixel(width-j,height-i);

                            dcMem.SetPixel(j,i,color2);

                            dcMem.SetPixel(width-j,height-i,color1);

                     }    

              }*/