Programming Windows程式开发设计指南->第五章 例子程序1

/*_############################################################################
  _##
  _##  Programming Windows程式开发设计指南->第五章 例子程序1
  _##  Author: xwlee                        
  _##  Time: 2007.06.17 
  _##  Chang'an University
  _##  Development condition: win2003 Server+VC6.0
  _##
  _##  程序5-1  DEVCAPS
  _##  DEVCAPS.C 文件
  _##  程序显示了以一个视频显示器的设备环境为参数时，
  _##  可以从 GetDeviceCaps函数中获得的部分信息
  _## 
  _## 
  _## 
  _##
  _##
  _##
  _##    DEVCAPS.C -- Device Capabilities Display Program No. 1
  _##     (c) Charles Petzold, 1998
  _##  
  _##########################################################################*/

#include <windows.h>

#define NUMLINES ((int) (sizeof devcaps / sizeof devcaps [0]))

struct

{

       int    iIndex ;

       TCHAR *       szLabel ;

       TCHAR *       szDesc ;

}

devcaps [] =
{
    // 以毫米计的实际屏幕的宽度 
 HORZSIZE,    TEXT ("HORZSIZE"),TEXT ("Width in millimeters:"),

    // 以毫米计的实际屏幕的高度
    VERTSIZE,    TEXT ("VERTSIZE"),TEXT ("Height in millimeters:"),

       HORZRES,     TEXT ("HORZRES"),    TEXT ("Width in pixels:"),

      VERTRES,     TEXT ("VERTRES"),    TEXT ("Height in raster lines:"),

       BITSPIXEL, TEXT ("BITSPIXEL"),TEXT ("Color bits per pixel:"),

       PLANES,       TEXT ("PLANES"),   TEXT ("Number of color planes:"),

      NUMBRUSHES,     TEXT ("NUMBRUSHES"),    TEXT ("Number of device brushes:"),

       NUMPENS,    TEXT ("NUMPENS"),        TEXT ("Number of device pens:"),

      NUMMARKERS,   TEXT ("NUMMARKERS"),  TEXT ("Number of device markers:"),

       NUMFONTS, TEXT ("NUMFONTS"),      TEXT ("Number of device fonts:"),

       NUMCOLORS,      TEXT ("NUMCOLORS"),     TEXT ("Number of device colors:"),

       PDEVICESIZE,      TEXT ("PDEVICESIZE"),     TEXT ("Size of device structure:"),

       // 最后，来自GetDeviceCaps的另三个值与视频大小有关。ASPECTX、ASPECTY和ASPECTXY
    // 值是每一个像素的相对宽度、高度和对角线大小，四舍五入到整数。对于正方形像素，
    // ASPECTX和ASPECTY值相同。无论如何，ASPECTXY值应等于ASPECTX与ASPECTY平方和的
    // 平方根，就像直角三角形一样。
    ASPECTX,    TEXT ("ASPECTX"),   TEXT ("Relative width of pixel:"),
       ASPECTY,     TEXT ("ASPECTY"),    TEXT ("Relative height of pixel:"),
       ASPECTXY,   TEXT ("ASPECTXY"),  TEXT ("Relative diagonal of pixel:"),

       LOGPIXELSX,      TEXT ("LOGPIXELSX"),     TEXT ("Horizontal dots per inch:"),

       LOGPIXELSY,       TEXT ("LOGPIXELSY"),     TEXT ("Vertical dots per inch:"),

       SIZEPALETTE,     TEXT ("SIZEPALETTE"),    TEXT ("Number of palette entries:"),

       NUMRESERVED,  TEXT ("NUMRESERVED"), TEXT ("Reserved palette entries:"),

       COLORRES, TEXT ("COLORRES"),        TEXT ("Actual color resolution:")

} ;

 

LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;

int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,
            PSTR szCmdLine, int iCmdShow)
{
       static TCHAR szAppName[] = TEXT ("DevCaps1") ;
       HWND          hwnd ;
       MSG             msg ;
       WNDCLASS wndclass ;
  
       wndclass.style              = CS_HREDRAW | CS_VREDRAW | CS_OWNDC;
       wndclass.lpfnWndProc= WndProc ;
       wndclass.cbClsExtra     = 0 ;
       wndclass.cbWndExtra = 0 ;
       wndclass.hInstance      = hInstance ;
       wndclass.hIcon            = LoadIcon (NULL, IDI_APPLICATION) ;
       wndclass.hCursor  = LoadCursor (NULL, IDC_ARROW) ;
       wndclass.hbrBackground      = (HBRUSH) GetStockObject (WHITE_BRUSH) ;
       wndclass.lpszMenuName      = NULL ;
       wndclass.lpszClassName       = szAppName ;
    
       if (!RegisterClass (&wndclass))
       {
              MessageBox ( NULL, TEXT ("This program requires Windows NT!"),
                                       szAppName, MB_ICONERROR) ;
              return 0 ;
     }

       hwnd = CreateWindow (       szAppName, TEXT ("Device Capabilities"),
                                            WS_OVERLAPPEDWINDOW,
                                      CW_USEDEFAULT, CW_USEDEFAULT,
                                    CW_USEDEFAULT, CW_USEDEFAULT,
                          NULL, NULL, hInstance, NULL) ;

       ShowWindow (hwnd, iCmdShow) ;
       UpdateWindow (hwnd) ;
    
       while (GetMessage (&msg, NULL, 0, 0))
     {
              TranslateMessage (&msg) ;
              DispatchMessage (&msg) ;
       }

       return msg.wParam ;
}

 
LRESULT CALLBACK WndProc (HWND hwnd, UINT message, WPARAM wParam, LPARAM lParam)
{
       static int  cxChar, cxCaps, cyChar ;
       TCHAR         szBuffer[10] ;
       HDC              hdc ;
       int           i ;
       PAINTSTRUCT     ps ;
       TEXTMETRIC      tm ;

      switch (message)
     {
       case WM_CREATE:
              hdc = GetDC (hwnd) ;

              GetTextMetrics (hdc, &tm) ;
              cxChar    = tm.tmAveCharWidth ;
              cxCaps    = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2 ;
              cyChar    = tm.tmHeight + tm.tmExternalLeading ;

             
     ReleaseDC (hwnd, hdc) ;
              return 0 ;

       case WM_PAINT:
              hdc = BeginPaint (hwnd, &ps) ;
              for (i = 0 ; i < NUMLINES ; i++)
              {
                     TextOut (       hdc, 0, cyChar * i,
                            devcaps[i].szLabel,
                            lstrlen (devcaps[i].szLabel)) ;
             
                     TextOut (       hdc, 14 * cxCaps, cyChar * i,
                            devcaps[i].szDesc,
                            lstrlen (devcaps[i].szDesc)) ;

                     SetTextAlign (hdc, TA_RIGHT | TA_TOP) ;
                     TextOut (hdc, 14*cxCaps+35*cxChar, cyChar*i, szBuffer,
                            wsprintf (szBuffer, TEXT ("%5d"),
                            GetDeviceCaps (hdc, devcaps[i].iIndex))) ;

             SetTextAlign (hdc, TA_LEFT | TA_TOP) ;
              }
       
              EndPaint (hwnd, &ps) ;
              return 0 ;

       case WM_DESTROY:
              PostQuitMessage (0) ;
              return 0 ;
       }

       return DefWindowProc (hwnd, message, wParam, lParam) ;
}