读取：   

  1、从数据库字段中取得大二进制位图数据；   

  2、在system的temp目录创建改位图文件；   

  3、在对话框中利用StretchBit显示位图；   

  存储：   

  1、利用文件选择对话框选择位图文件；   

  2、显示；   

  3、点击插入后存储到数据库中   

    

  以下是取和存的函数，具体操作大二进制文件的方法，可具体参照一些文档，vckbase有的   

    

  //取出位图文件并保存于临时文件   

  CString   CStlibPage3::OperateBitmap(CString   m_strname)   

  {   

            CStandardSet*   m_pStandard   =   new   CStandardSet();       

            m_pStandard->Open();         

            if   (m_pStandard->GetRecordCount()!=0)           

                    m_pStandard->MoveFirst();   

            int   tempnumber   =   0;           

            CByteArray   Array1;     

            while   (!m_pStandard->IsEOF())     

            {                   

                      if(m_pStandard->m_StandardName   ==   m_standard_name)               

                      {                   

                              Array1.Copy(m_pStandard->m_StabitmapFile);   

                              tempnumber   =   Array1.GetSize();       

                              break;             

                      }               

                      m_pStandard->MoveNext();       

          }         

          m_pStandard->Close();     

          delete   m_pStandard;     

          DWORD   dwWritten;     

          //**********************************************     

          char   temp_name[_MAX_PATH];       

          GetTempPath(_MAX_PATH,temp_name);   

          strcat(temp_name,"bitmap.tmp");   

          HANDLE   fh;     

          for   (int   nIndex   =   0;   nIndex   <   tempnumber;   nIndex++)     

          {                   

                    if   (Array1.GetAt(nIndex)   ==   'B'   &&   Array1.GetAt(nIndex   +   1)   ==   'M'   

                              &&   Array1.GetAt(nIndex   +   2)   !=   'P')         

                    {       

                                int   HeaderLen   =       nIndex;//   +   sizeof(BITMAPFILEHEADER);       

                                Array1.RemoveAt(   0,   HeaderLen   );   

                                break;             

                    }         

          }             

          LPBITMAPINFOHEADER   bmiHeader   =   (LPBITMAPINFOHEADER)Array1.GetData()   ;     

          fh   =   CreateFile(temp_name,GENERIC_WRITE,0,NULL,CREATE_ALWAYS,   

                                        FILE_ATTRIBUTE_NORMAL|FILE_FLAG_SEQUENTIAL_SCAN,NULL);   

          WriteFile(fh,(LPBYTE)bmiHeader,(DWORD)tempnumber,&dwWritten,NULL);     

          Array1.RemoveAll();   //Relese   Memory   

          CloseHandle(fh);       

          return   temp_name;   

    }       

    

    void   CStlibPage3::Savebmp_Data()   

    {       

        CStandardSet*   m_pStandard   =   new   CStandardSet();     

        m_pStandard->Open();   

        CString   tempid   =   "StandardName   =   '"   +   m_standard_name+"'";   

        if(m_pStandard->FindLast(tempid))     

        {       

                if   (strBitmapPath   ==   "")     

                {           

                      if   (!m_pStandard->CanUpdate())   return;   

                          m_pStandard->Edit();   

                      CString   strupdate   =   "NULL";   

                      m_pStandard->SetFieldValue(_T("[StabitmapFile]"),COleVariant(strupdate));   

                      m_pStandard->Update();   

                      goto   ip;           

                }             

                CFile   tempfile;       

                tempfile.Open(strBitmapPath,CFile::modeRead);   

                DWORD   dwBufSize;     

                dwBufSize   =   tempfile.GetLength();   

                Array.SetSize(dwBufSize);             

                tempfile.ReadHuge((LPSTR)(Array.GetData()),   dwBufSize);   

                tempfile.Close();       

                (m_pStandard->m_StabitmapFile).Copy(Array);   

                if   (!m_pStandard->CanUpdate())   return;         

                m_pStandard->Edit();       

                m_pStandard->SetFieldValue(_T("[StabitmapFile]"),COleVariant(Array));     

                m_pStandard->Update();             

        }   

  ip:       

        m_pStandard->Close();     

        delete   m_pStandard;   

    }             

    

  void   CStlibPage3::DrawBitmap()   

  {   

  UpdateData(TRUE);   

  //draw   bitmap   

  if   (CStlibPage3::hpreview)   

                  DeleteObject(CStlibPage3::hpreview);   

          CStlibPage3::hpreview   =   (HBITMAP)LoadImage(AfxGetInstanceHandle(),strBitmapPath,IMAGE_BITMAP,0,0,LR_LOADFROMFILE|LR_CREATEDIBSECTION);   

  if   (CStlibPage3::hpreview)   

        {   

                                    

                  GetObject(CStlibPage3::hpreview,sizeof(BITMAP),&bm);   

    

                  CSize   m_sizeSource(bm.bmWidth,bm.bmHeight);   

  GetDlgItem(IDC_PIC_PREVIEW)->GetClientRect(&m_rectDest);   

    

  CClientDC   pDC(GetDlgItem(IDC_PIC_PREVIEW));   

  HDC   dcmem   =   CreateCompatibleDC(pDC);   

  HBITMAP   old   =   (HBITMAP)SelectObject(dcmem,CStlibPage3::hpreview);   

    

                  StretchBlt(pDC.m_hDC,m_rectDest.left,   m_rectDest.top,   m_rectDest.Width(),   m_rectDest.Height(),dcmem,0,0,bm.bmWidth,bm.bmHeight,SRCCOPY);   

  //GetDlgItem(IDC_PIC_PREVIEW)->GetDC()   

                  SelectObject(dcmem,old);   

    

                  DeleteDC(dcmem);   

          }   

  }   

typedef struct 

{

    UINT    uImageLen;   

    unsigned char   *pbyImage;                        

}PIC,*PPIC;



FILE* fp = fopen("C:\\Documents and Settings\\Administrator\\My Documents\\My Pictures\\cc.jpg", "wb");

if (fp)

{  

    PPIC pPic;

    fseek(fp,   0,   2);   

    pPic->uImageLen   =   ftell(fp);

    pPic->pbyImage = new unsigned char(pPic->uImageLen);

    fwrite(pPic->pbyImage, 1, pPic->uImageLen, fp);

    fclose(fp);

}else

    AfxMessageBox("error");