13. 使用打印机.txt

本书介绍了在Microsoft Windows 98、Microsoft Windows NT 4.0和Windows NT 5.0下程序写作的方法

        
           }
        
           return msg.wParam ;
        
}
        

LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam,LPARAM lParam)
        
{
        
   static TCHAR                          szDevice[32], szWindowText[64] ;
        
    static int                           cxChar, cyChar,nCurrentDevice        = IDM_SCREEN,
        
       nCurrentInfo       = IDM_BASIC ;
        
           static DWORD                         dwNeeded, dwReturned ;
        
           static PRINTER_INFO_4 * pinfo4 ;
        
           static PRINTER_INFO_5 * pinfo5 ;
        
           DWORD                  i ;
        
           HDC                    hdc, hdcInfo ;
        
           HMENU                 hMenu ;
        
           HANDLE                 hPrint ;
        
           PAINTSTRUCT            ps ;
        
           TEXTMETRIC            tm ;
        
   
        
           switch (message)
        
           {
        
           case   WM_CREATE :
        
                          hdc =  GetDC (hwnd) ;
        
                   SelectObject (hdc, GetStockObject (SYSTEM_FIXED_FONT)) ;
        
                   GetTextMetrics (hdc, &tm) ;
        
                          cxChar = tm.tmAveCharWidth ;
        
                          cyChar = tm.tmHeight + tm.tmExternalLeading ;
        
                          ReleaseDC (hwnd, hdc) ;
        
// fall through
        
           case   WM_SETTINGCHANGE:
        
                          hMenu = GetSubMenu (GetMenu (hwnd), 0) ;
        
        
        
                          while (GetMenuItemCount (hMenu) > 1)
        
                                  DeleteMenu (hMenu, 1, MF_BYPOSITION) ;
        

                                  // Get a list of all local and remote printers
        
                                  //
        
                                 // First, find out how large an array we need; this
        
                                  //   call will fail, leaving the required size in dwNeeded
        
                                  //
        
                                 // Next, allocate space for the info array and fill it
        
                                  //
        
                                 // Put the printer names on the menu
        

            if (GetVersion () & 0x80000000)                                     // Windows 98
        
                  {
        
                                  EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 5, NULL,
        
                       0, &dwNeeded, &dwReturned) ;
        

                                 pinfo5 = malloc (dwNeeded) ;
        

                                  EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 5, (PBYTE) pinfo5,
        
                       dwNeeded, &dwNeeded, &dwReturned) ;
        

                                  for (i = 0 ; i < dwReturned ; i++)
        
                                  {
        
                                        AppendMenu (hMenu, (i+1) % 16 ? 0 : MF_MENUBARBREAK, i + 1,
        
                                                                                    pinfo5[i].pPrinterName) ;
        
                                  }
        
                                free (pinfo5) ;
        
          }
        
                  else
        
// Windows NT
        
         {
        
                                 EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 4, NULL,
        
                       0, &dwNeeded, &dwReturned) ;
        
                                  pinfo4 = malloc (dwNeeded) ;
        
                                  EnumPrinters (PRINTER_ENUM_LOCAL, NULL, 4, (PBYTE) pinfo4,
        
                      dwNeeded, &dwNeeded, &dwReturned) ;
        
                                  for (i = 0 ; i < dwReturned ; i++)
        
                                         {
        
                                   AppendMenu (hMenu, (i+1) % 16 ? 0 : MF_MENUBARBREAK, i + 1,
        
                                        pinfo4[i].pPrinterName) ;
        
              }
        
                                         free (pinfo4) ;
        
                  }
        
        
        
                  AppendMenu (hMenu, MF_SEPARATOR, 0, NULL) ;
        
                  AppendMenu (hMenu, 0, IDM_DEVMODE, TEXT ("Properties")) ;
        
        
        
                  wParam = IDM_SCREEN ;
        
// fall through
        
           case   WM_COMMAND :
        
                          hMenu = GetMenu (hwnd) ;
        
        
        
                          if (   LOWORD (wParam) == IDM_SCREEN ||     // IDM_SCREEN & Printers
        
                                         LOWORD (wParam) < IDM_DEVMODE)     
        
                          {
        
                          CheckMenuItem (hMenu, nCurrentDevice, MF_UNCHECKED) ;
        
                          nCurrentDevice = LOWORD (wParam) ;
        
                          CheckMenuItem (hMenu, nCurrentDevice, MF_CHECKED) ;
        
                          }
        
                          else if (LOWORD (wParam) == IDM_DEVMODE)     // Properties selection
        
                          {
        
                                                 GetMenuString (hMenu, nCurrentDevice, szDevice,
        
                                  sizeof (szDevice) / sizeof (TCHAR), MF_BYCOMMAND);
        
             
        
                                                 if (OpenPrinter (szDevice, &hPrint, NULL))
        
                                                 {
        
                                                 PrinterProperties (hwnd, hPrint) ;
        
                                                 ClosePrinter (hPrint) ;
        
                                                 }
        
                          }
        
                          else
        
// info menu items
        
         {
        
                                         CheckMenuItem (hMenu, nCurrentInfo, MF_UNCHECKED) ;
        
                                         nCurrentInfo = LOWORD (wParam) ;
        
                                         CheckMenuItem (hMenu, nCurrentInfo, MF_CHECKED) ;
        
                          }
        
                          InvalidateRect (hwnd, NULL, TRUE) ;
        
                          return 0 ;
        
       
        
           case   WM_INITMENUPOPUP :
        
                          if (lParam == 0)
        
                                                EnableMenuItem (GetMenu (hwnd), IDM_DEVMODE,
        
                                                         nCurrentDevice == IDM_SCREEMF_GRAYED : MF_ENABLED) ;
        
                          return 0 ;
        
        
        
           case   WM_PAINT :
        
                          lstrcpy (szWindowText, TEXT ("Device Capabilities: ")) ;
        
        
        
                          if (nCurrentDevice == IDM_SCREEN)
        
                          {
        
                                         lstrcpy (szDevice, TEXT ("DISPLAY")) ;
        
                                         hdcInfo = CreateIC (szDevice, NULL, NULL, NULL) ;
        
                          }
        
                          else
        
                          {
        
                                         hMenu = GetMenu (hwnd) ;
        
                                         GetMenuString (hMenu, nCurrentDevice, szDevice,
        
                           sizeof (szDevice), MF_BYCOMMAND) ;
        
                                        hdcInfo = CreateIC (NULL, szDevice, NULL, NULL) ;
        
                          }
        
        
        
                          lstrcat (szWindowText, szDevice) ;
        
                          SetWindowText (hwnd, szWindowText) ;
        
        
        
                          hdc = BeginPaint (hwnd, &ps) ;
        
                          SelectObject (hdc, GetStockObject (SYSTEM_FIXED_FONT)) ;
        
        
        
                          if (hdcInfo)
        
                          {
        
                                         switch (nCurrentInfo)
        
                                                {
        
                                         case   IDM_BASIC :
        
                          DoBasicInfo (hdc, hdcInfo, cxChar, cyChar) ;
        
                                                         break ;
        
                  
        
                                  case   IDM_OTHER :
        
                          DoOtherInfo (hdc, hdcInfo, cxChar, cyChar) ;
        
                                                break ;
        
                  
        
                                 case   IDM_CURVE :
        
                                  case   IDM_LINE :
        
                                  case   IDM_POLY :
        
                                  case   IDM_TEXT :
        
                          DoBitCodedCaps (hdc, hdcInfo, cxChar, cyChar,
        
                                        nCurrentInfo - IDM_CURVE) ;
        
                                                 break ;
        
                                         }
        
                                  DeleteDC (hdcInfo) ;
        
                  }
        
        
        
                  EndPaint (hwnd, &ps) ;