WindowsAPI学习记录(键盘消息)

下面的代码是来自于书上的，我那就按照自己的理解给下面的代码来一个自己的成果总结。

下面是一个头文件sysmets.h

/*-----------------------------------------------   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 dragable width"),     SM_CYMAXTRACK,           TEXT ("SM_CYMAXTRACK"),                                          TEXT ("Maximum dragable 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")} ;

下面是源码

/*----------------------------------------------------   SYSMETS4.C -- System Metrics Display Program No. 4                 (c) Charles Petzold, 1998  ----------------------------------------------------*/#define WINVER 0x0500#include <windows.h>#include "sysmets.h"LRESULT CALLBACK WndProc (HWND,UINT,WPARAM,LPARAM);//回调函数的声明int WINAPI WinMain(HINSTANCE hInstance,//当前实例句柄

HINSTANCE hPrevInstance,//先前实例句柄

LPSTR szCmdLine,//命令行

int iCmdShow)//显示状态{static TCHAR szAppName[]=TEXT("Sysmets4");HWND hwnd;//当前实例的句炳MSG msg;//消息WNDCLASS wndclass;//窗口类名wndclass.style=CS_HREDRAW | CS_VREDRAW;//窗口风格，分别为水平重画和竖直重画
wndclass.cbClsExtra=0;//窗口扩展，一般为0wndclass.cbWndExtra=0;//窗口实例扩展，一般为0wndclass.hbrBackground=(HBRUSH)GetStockObject(WHITE_BRUSH);//窗口背景颜色，此处为白色wndclass.hCursor=LoadCursor(NULL,IDC_ARROW);//窗口图标wndclass.hIcon=LoadIcon(NULL,IDI_APPLICATION);//窗口鼠标光标wndclass.hInstance=hInstance;//实例句柄wndclass.lpfnWndProc=WndProc;//回调函数wndclass.lpszClassName=szAppName;//窗口类的名字wndclass.lpszMenuName=NULL;//菜单名，此处没有if(!RegisterClass(&wndclass))//注册窗口{MessageBox(NULL,TEXT("Program requires Windows NT!"),szAppName,MB_ICONERROR);return 0;}hwnd=CreateWindow(szAppName,TEXT("Get System Metrics No.4"),//创建窗口WS_OVERLAPPEDWINDOW | WS_VSCROLL | WS_HSCROLL,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,hInstance,NULL);ShowWindow(hwnd,iCmdShow);//显示窗口UpdateWindow(hwnd);//更新窗口while(GetMessage(&msg,NULL,0,0))//消息循环{TranslateMessage(&msg);DispatchMessage(&msg);}return msg.wParam;}LRESULT CALLBACK WndProc(HWND hwnd,UINT message,WPARAM wParam,LPARAM lParam){static int cxChar,cyChar,cxCaps,cxClient,cyClient,iMaxWidth;HDC hdc;int i,x,y,iVertPos,iHorzPos,iPaintBeg,iPaintEnd;PAINTSTRUCT ps;//绘图结构SCROLLINFO si;//滚动条结构TCHAR szBuffer[10];//字符串TEXTMETRIC tm;//字体信息结构switch(message){case WM_CREATE:hdc=GetDC(hwnd);GetTextMetrics(hdc,&tm);//获取系统字体信息，用tm来保存cxChar=tm.tmAveCharWidth;//平均字符的宽度cyChar=tm.tmHeight+tm.tmExternalLeading;//字符总高度=字符平均高度+字符间距

cxCaps=(tm.tmPitchAndFamily&1?3:2)*cxChar/2;//大写字符的平均宽度ReleaseDC(hwnd,hdc);//获取环境信息之后，释放句柄iMaxWidth=40*cxChar+22*cxCaps;//窗口总宽度return 0;case WM_SIZE:cxClient=LOWORD(lParam);//窗口宽度cyClient=HIWORD(lParam);//窗口高度si.cbSize=sizeof(si);si.fMask=SIF_RANGE | SIF_PAGE;si.nMax=NUMLINES-1;si.nMin=0;si.nPage=cyClient/cyChar;SetScrollInfo(hwnd,SB_VERT,&si,TRUE);//修改竖直滚动条的信息si.cbSize=sizeof(si);si.fMask=SIF_RANGE | SIF_PAGE;si.nMin=0;si.nMax=2+iMaxWidth / cxChar;si.nPage=cxClient/cxChar;SetScrollInfo(hwnd,SB_HORZ,&si,TRUE);//修改水平滚动条的信息return 0;case WM_VSCROLL:si.cbSize=sizeof(si);si.fMask=SIF_ALL;GetScrollInfo(hwnd,SB_VERT,&si);//获取竖直滚动条的消息iVertPos=si.nPos;switch(LOWORD(wParam)){case SB_TOP:si.nPos=si.nMin;break;case SB_BOTTOM:si.nPos=si.nMax;break;case SB_LINEUP:si.nPos-=1;break;case SB_LINEDOWN:si.nPos+=1;break;case SB_PAGEUP:si.nPos-=si.nPage;break;case SB_PAGEDOWN:si.nPos+=si.nPage;case SB_THUMBTRACK:si.nPos=si.nTrackPos;break;default:break;}si.fMask=SIF_POS;SetScrollInfo(hwnd,SB_VERT,&si,TRUE);//重新修改操作之后的竖直滚动条的信息GetScrollInfo(hwnd,SB_VERT,&si);//获取改动后的信息if(si.nPos!=iVertPos){ScrollWindow(hwnd,0,cyChar*(iVertPos-si.nPos),NULL,NULL);UpdateWindow(hwnd);}return 0;case WM_HSCROLL:si.cbSize=sizeof(si);si.fMask=SIF_ALL;GetScrollInfo(hwnd,SB_HORZ,&si);//获取水平滚动条的信息iHorzPos=si.nPos;switch(LOWORD(wParam)){case SB_LINELEFT:si.nPos-=1;break;case SB_LINERIGHT:si.nPos+=1;break;case SB_PAGELEFT:si.nPos-=si.nPage;break;case SB_PAGERIGHT:si.nPos+=si.nPage;break;case SB_THUMBPOSITION:si.nPos=si.nTrackPos;break;default:break;}si.fMask=SIF_POS;SetScrollInfo(hwnd,SB_HORZ,&si,TRUE);//修改操作后的水平滚动条的信息GetScrollInfo(hwnd,SB_HORZ,&si);//获取改动后的消息if(si.nPos!=iHorzPos){ScrollWindow(hwnd,cxChar*(iHorzPos-si.nPos),0,NULL,NULL);}return 0;case WM_KEYDOWN://按键操作，把按键的信息通过SendMessage函数传递给滚动条，进而操纵滚动条switch(wParam){case VK_HOME:SendMessage(hwnd,WM_VSCROLL,SB_TOP,0);break;case VK_END:SendMessage(hwnd,WM_VSCROLL,SB_BOTTOM,0);break;case VK_PRIOR:SendMessage(hwnd,WM_VSCROLL,SB_PAGEUP,0);break;case VK_NEXT:SendMessage(hwnd,WM_VSCROLL,SB_PAGEDOWN,0);break;case VK_UP:SendMessage(hwnd,WM_VSCROLL,SB_LINEUP,0);break;case VK_DOWN:SendMessage(hwnd,WM_VSCROLL,SB_LINEDOWN,0);break;case VK_LEFT:SendMessage(hwnd,WM_HSCROLL,SB_PAGEUP,0);break;case VK_RIGHT:SendMessage(hwnd,WM_HSCROLL,SB_PAGERIGHT,0);break;}return 0;case WM_PAINT://绘制窗口hdc=BeginPaint(hwnd,&ps);si.cbSize=sizeof(si);si.fMask=SIF_POS;GetScrollInfo(hwnd,SB_VERT,&si);iVertPos=si.nPos;GetScrollInfo(hwnd,SB_HORZ,&si);iHorzPos=si.nPos;iPaintBeg = max (0, iVertPos + ps.rcPaint.top / cyChar) ;//max(0,当前位置+需要绘图的矩形区的最高点/字符的高度)  iPaintEnd = min (NUMLINES - 1,                           iVertPos + ps.rcPaint.bottom / cyChar) ;//绘图结束的地方 = 当前位置+绘制去取的高度          for (i = iPaintBeg ; i <= iPaintEnd ; i++){               x = cxChar * (1 - iHorzPos) ;               y = cyChar * (i - iVertPos) ;                              TextOut (hdc, x, y,                        sysmetrics[i].szLabel,                        lstrlen (sysmetrics[i].szLabel)) ;                              TextOut (hdc, x + 22 * cxCaps, y,                        sysmetrics[i].szDesc,                        lstrlen (sysmetrics[i].szDesc)) ;                              SetTextAlign (hdc, TA_RIGHT | TA_TOP) ;                              TextOut (hdc, x + 22 * cxCaps + 40 * cxChar, y, 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);}