首页 > 代码库 > windows程序设计读书笔记2——字符显示1

windows程序设计读书笔记2——字符显示1

本程序使用GetSystemMetrics获取windows各种图像选项,并输出字符到窗口中。
#define WINVER 0x0500#include <windows.h>#include "sysmets.h"LRESULT CALLBACK WndProc (HWND, UINT, WPARAM, LPARAM) ;int WINAPI WinMain (HINSTANCE hInstance, HINSTANCE hPrevInstance,                    PSTR szCmdLine, int iCmdShow){     static TCHAR szAppName[] = TEXT ("SysMets1") ;     HWND         hwnd ;     MSG          msg ;     WNDCLASS     wndclass ;     wndclass.style         = CS_HREDRAW | CS_VREDRAW ;     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 ("Get System Metrics No. 1"),                          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 ;     HDC         hdc ;     int         i ;     PAINTSTRUCT ps ;     TCHAR       szBuffer [10] ;     TEXTMETRIC  tm ;     switch (message)     {     case WM_CREATE:          hdc = GetDC (hwnd) ;          GetTextMetrics (hdc, &tm) ;          cxChar = tm.tmAveCharWidth ;   // 平均字符宽度          cxCaps = (tm.tmPitchAndFamily & 1 ? 3 : 2) * cxChar / 2 ; // 字体间距(低4位)和族(高4位)          cyChar = tm.tmHeight + tm.tmExternalLeading ;  // 字符高度 + 夹在两行之间的空间数目          ReleaseDC (hwnd, hdc) ;          return 0 ;     case WM_PAINT :          hdc = BeginPaint (hwnd, &ps) ;          for (i = 0 ; i < NUMLINES ; i++)          {               TextOut (hdc, 0, cyChar * i,                                              sysmetrics[i].szLabel,                        lstrlen (sysmetrics[i].szLabel)) ;               TextOut (hdc, 22 * cxCaps, cyChar * i,                              sysmetrics[i].szDesc,                        lstrlen (sysmetrics[i].szDesc)) ;               SetTextAlign (hdc, TA_RIGHT | TA_TOP) ;               TextOut (hdc, 22 * cxCaps + 40 * cxChar, cyChar * i, szBuffer,                        wsprintf (szBuffer, TEXT ("%5d"),                             GetSystemMetrics (sysmetrics[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) ;}

在创建窗口时使用GetTextMetrics函数获取用户界面尺寸,获取设备上下文,包括字符宽度、高度等。

关于TEXTMETRIC结构体,定义如下:

typedef struct tagTEXTMETRIC {  LONG  tmHeight;  LONG  tmAscent;  LONG  tmDescent;  LONG  tmInternalLeading;  LONG  tmExternalLeading;  LONG  tmAveCharWidth;  LONG  tmMaxCharWidth;  LONG  tmWeight;  LONG  tmOverhang;  LONG  tmDigitizedAspectX;  LONG  tmDigitizedAspectY;  TCHAR tmFirstChar;  TCHAR tmLastChar;  TCHAR tmDefaultChar;  TCHAR tmBreakChar;  BYTE  tmItalic;  BYTE  tmUnderlined;  BYTE  tmStruckOut;  BYTE  tmPitchAndFamily;  BYTE  tmCharSet;} TEXTMETRIC, *PTEXTMETRIC;

在绘图时,使用GetSystemMetrics获取系统图形信息,再调用TextOut函数输出文本至窗口。

int WINAPI GetSystemMetrics(  __in  int nIndex);

这里我们在头文件定义了sysmetrics数组,把需要得到的系统数据或者系统配置信息名称写好。

/*-----------------------------------------------   SYSMETS.H -- System metrics display structure  -----------------------------------------------*/#define NUMLINES ((int) (sizeof sysmetrics / sizeof sysmetrics [0]))struct{      int     iIndex ;     TCHAR * szLabel ;     TCHAR * szDesc ;}sysmetrics [] ={     SM_CXSCREEN,             TEXT ("SM_CXSCREEN"),                                            TEXT ("Screen width in pixels"),     SM_CYSCREEN,             TEXT ("SM_CYSCREEN"),                                            TEXT ("Screen height in pixels"),     SM_CXVSCROLL,            TEXT ("SM_CXVSCROLL"),                                           TEXT ("Vertical scroll width"),     SM_CYHSCROLL,            TEXT ("SM_CYHSCROLL"),                                           TEXT ("Horizontal scroll height"),     SM_CYCAPTION,            TEXT ("SM_CYCAPTION"),                                           TEXT ("Caption bar height"),     SM_CXBORDER,             TEXT ("SM_CXBORDER"),                                            TEXT ("Window border width"),     SM_CYBORDER,             TEXT ("SM_CYBORDER"),                                            TEXT ("Window border height"),     SM_CXFIXEDFRAME,         TEXT ("SM_CXFIXEDFRAME"),                                        TEXT ("Dialog window frame width"),     SM_CYFIXEDFRAME,         TEXT ("SM_CYFIXEDFRAME"),                                        TEXT ("Dialog window frame height"),     SM_CYVTHUMB,             TEXT ("SM_CYVTHUMB"),                                            TEXT ("Vertical scroll thumb height"),     SM_CXHTHUMB,             TEXT ("SM_CXHTHUMB"),                                            TEXT ("Horizontal scroll thumb width"),     SM_CXICON,               TEXT ("SM_CXICON"),                                              TEXT ("Icon width"),     SM_CYICON,               TEXT ("SM_CYICON"),                                              TEXT ("Icon height"),     SM_CXCURSOR,             TEXT ("SM_CXCURSOR"),                                            TEXT ("Cursor width"),     SM_CYCURSOR,             TEXT ("SM_CYCURSOR"),                                            TEXT ("Cursor height"),     SM_CYMENU,               TEXT ("SM_CYMENU"),                                              TEXT ("Menu bar height"),     SM_CXFULLSCREEN,         TEXT ("SM_CXFULLSCREEN"),                                        TEXT ("Full screen client area width"),     SM_CYFULLSCREEN,         TEXT ("SM_CYFULLSCREEN"),                                        TEXT ("Full screen client area height"),     SM_CYKANJIWINDOW,        TEXT ("SM_CYKANJIWINDOW"),                                       TEXT ("Kanji window height"),     SM_MOUSEPRESENT,         TEXT ("SM_MOUSEPRESENT"),                                        TEXT ("Mouse present flag"),     SM_CYVSCROLL,            TEXT ("SM_CYVSCROLL"),                                           TEXT ("Vertical scroll arrow height"),     SM_CXHSCROLL,            TEXT ("SM_CXHSCROLL"),                                           TEXT ("Horizontal scroll arrow width"),     SM_DEBUG,                TEXT ("SM_DEBUG"),                                               TEXT ("Debug version flag"),     SM_SWAPBUTTON,           TEXT ("SM_SWAPBUTTON"),                                          TEXT ("Mouse buttons swapped flag"),     SM_CXMIN,                TEXT ("SM_CXMIN"),                                               TEXT ("Minimum window width"),     SM_CYMIN,                TEXT ("SM_CYMIN"),                                               TEXT ("Minimum window height"),     SM_CXSIZE,               TEXT ("SM_CXSIZE"),                                              TEXT ("Min/Max/Close button width"),     SM_CYSIZE,               TEXT ("SM_CYSIZE"),                                              TEXT ("Min/Max/Close button height"),     SM_CXSIZEFRAME,          TEXT ("SM_CXSIZEFRAME"),                                         TEXT ("Window sizing frame width"),     SM_CYSIZEFRAME,          TEXT ("SM_CYSIZEFRAME"),                                         TEXT ("Window sizing frame height"),     SM_CXMINTRACK,           TEXT ("SM_CXMINTRACK"),                                          TEXT ("Minimum window tracking width"),     SM_CYMINTRACK,           TEXT ("SM_CYMINTRACK"),                                          TEXT ("Minimum window tracking height"),     SM_CXDOUBLECLK,          TEXT ("SM_CXDOUBLECLK"),                                         TEXT ("Double click x tolerance"),     SM_CYDOUBLECLK,          TEXT ("SM_CYDOUBLECLK"),                                         TEXT ("Double click y tolerance"),     SM_CXICONSPACING,        TEXT ("SM_CXICONSPACING"),                                       TEXT ("Horizontal icon spacing"),     SM_CYICONSPACING,        TEXT ("SM_CYICONSPACING"),                                       TEXT ("Vertical icon spacing"),     SM_MENUDROPALIGNMENT,    TEXT ("SM_MENUDROPALIGNMENT"),                                   TEXT ("Left or right menu drop"),     SM_PENWINDOWS,           TEXT ("SM_PENWINDOWS"),                                          TEXT ("Pen extensions installed"),     SM_DBCSENABLED,          TEXT ("SM_DBCSENABLED"),                                         TEXT ("Double-Byte Char Set enabled"),     SM_CMOUSEBUTTONS,        TEXT ("SM_CMOUSEBUTTONS"),                                       TEXT ("Number of mouse buttons"),     SM_SECURE,               TEXT ("SM_SECURE"),                                              TEXT ("Security present flag"),     SM_CXEDGE,               TEXT ("SM_CXEDGE"),                                              TEXT ("3-D border width"),     SM_CYEDGE,               TEXT ("SM_CYEDGE"),                                              TEXT ("3-D border height"),     SM_CXMINSPACING,         TEXT ("SM_CXMINSPACING"),                                        TEXT ("Minimized window spacing width"),     SM_CYMINSPACING,         TEXT ("SM_CYMINSPACING"),                                        TEXT ("Minimized window spacing height"),     SM_CXSMICON,             TEXT ("SM_CXSMICON"),                                            TEXT ("Small icon width"),     SM_CYSMICON,             TEXT ("SM_CYSMICON"),                                            TEXT ("Small icon height"),     SM_CYSMCAPTION,          TEXT ("SM_CYSMCAPTION"),                                         TEXT ("Small caption height"),     SM_CXSMSIZE,             TEXT ("SM_CXSMSIZE"),                                            TEXT ("Small caption button width"),     SM_CYSMSIZE,             TEXT ("SM_CYSMSIZE"),                                            TEXT ("Small caption button height"),     SM_CXMENUSIZE,           TEXT ("SM_CXMENUSIZE"),                                          TEXT ("Menu bar button width"),     SM_CYMENUSIZE,           TEXT ("SM_CYMENUSIZE"),                                          TEXT ("Menu bar button height"),     SM_ARRANGE,              TEXT ("SM_ARRANGE"),                                             TEXT ("How minimized windows arranged"),     SM_CXMINIMIZED,          TEXT ("SM_CXMINIMIZED"),                                         TEXT ("Minimized window width"),     SM_CYMINIMIZED,          TEXT ("SM_CYMINIMIZED"),                                         TEXT ("Minimized window height"),     SM_CXMAXTRACK,           TEXT ("SM_CXMAXTRACK"),                                          TEXT ("Maximum draggable width"),     SM_CYMAXTRACK,           TEXT ("SM_CYMAXTRACK"),                                          TEXT ("Maximum draggable height"),     SM_CXMAXIMIZED,          TEXT ("SM_CXMAXIMIZED"),                                         TEXT ("Width of maximized window"),     SM_CYMAXIMIZED,          TEXT ("SM_CYMAXIMIZED"),                                         TEXT ("Height of maximized window"),     SM_NETWORK,              TEXT ("SM_NETWORK"),                                             TEXT ("Network present flag"),     SM_CLEANBOOT,            TEXT ("SM_CLEANBOOT"),                                           TEXT ("How system was booted"),     SM_CXDRAG,               TEXT ("SM_CXDRAG"),                                              TEXT ("Avoid drag x tolerance"),     SM_CYDRAG,               TEXT ("SM_CYDRAG"),                                              TEXT ("Avoid drag y tolerance"),     SM_SHOWSOUNDS,           TEXT ("SM_SHOWSOUNDS"),                                          TEXT ("Present sounds visually"),     SM_CXMENUCHECK,          TEXT ("SM_CXMENUCHECK"),                                         TEXT ("Menu check-mark width"),     SM_CYMENUCHECK,          TEXT ("SM_CYMENUCHECK"),                                         TEXT ("Menu check-mark height"),     SM_SLOWMACHINE,          TEXT ("SM_SLOWMACHINE"),                                         TEXT ("Slow processor flag"),     SM_MIDEASTENABLED,       TEXT ("SM_MIDEASTENABLED"),                                      TEXT ("Hebrew and Arabic enabled flag"),     SM_MOUSEWHEELPRESENT,    TEXT ("SM_MOUSEWHEELPRESENT"),                                   TEXT ("Mouse wheel present flag"),     SM_XVIRTUALSCREEN,       TEXT ("SM_XVIRTUALSCREEN"),                                      TEXT ("Virtual screen x origin"),     SM_YVIRTUALSCREEN,       TEXT ("SM_YVIRTUALSCREEN"),                                      TEXT ("Virtual screen y origin"),     SM_CXVIRTUALSCREEN,      TEXT ("SM_CXVIRTUALSCREEN"),                                     TEXT ("Virtual screen width"),     SM_CYVIRTUALSCREEN,      TEXT ("SM_CYVIRTUALSCREEN"),                                     TEXT ("Virtual screen height"),     SM_CMONITORS,            TEXT ("SM_CMONITORS"),                                           TEXT ("Number of monitors"),     SM_SAMEDISPLAYFORMAT,    TEXT ("SM_SAMEDISPLAYFORMAT"),                                   TEXT ("Same color format flag")} ;

整个程序结构与上一篇的几乎一致。

不过这个程序还是有很多不足,比如坐标通过直接定义,未考虑窗口尺寸大小,输出信息可能不能完全显示等,后面我们再通过修改程序进一步完善

windows程序设计读书笔记2——字符显示1