第四章、文本输出

头文件：

/*-----------------------------------------------
   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")
} ;

第一个版本滚动条：效率差

#include <Windows.h>
#include "SysMets.h"
#include <tchar.h>

HINSTANCE  g_hInst = NULL;

LRESULT CALLBACK ParentProc(HWND hWnd, UINT nMsg, WPARAM wParam, LPARAM lParam)
{
    static int cxChar, cyChar, cxCaps, cyClient, iVscrollPos;
    HDC hDC;
    int i, y;
    PAINTSTRUCT ps;
    TCHAR szBuffer[10] = {0};
    TEXTMETRIC tm;

    switch(nMsg)
    {
    case WM_CREATE:
        hDC = GetDC(hWnd);
        GetTextMetrics(hDC,&tm);
        cxChar = tm.tmAveCharWidth;
        cyChar = tm.tmHeight + tm.tmExternalLeading;
        cxCaps =(tm.tmPitchAndFamily & 1? 3: 2) * cxChar/2;
        ReleaseDC(hWnd,hDC);

        SetScrollRange(hWnd, SB_VERT, 0, NUMLINES -1, FALSE);
        SetScrollPos(hWnd, SB_VERT, iVscrollPos, TRUE);
        return 0;
    case WM_SIZE:
        cyClient = HIWORD(lParam);
        return 0;
    case WM_VSCROLL:
        switch(LOWORD(wParam))
        {
        case SB_LINEUP:
            iVscrollPos += 1;
            break;
        case SB_LINEDOWN:
            iVscrollPos -= 1;
            break;
        case SB_PAGEUP:
            iVscrollPos +=  cyClient/cyChar;
            break;
        case SB_PAGEDOWN:
            iVscrollPos -= cyClient/cyChar;
            break;
        case SB_THUMBTRACK:
            iVscrollPos = HIWORD(wParam);
            break;
        }

        iVscrollPos = max(0, min(iVscrollPos, NUMLINES -1));
        if(iVscrollPos != GetScrollPos(hWnd, SB_VERT))
        {
            SetScrollPos(hWnd, SB_VERT, iVscrollPos, TRUE);
            InvalidateRect(hWnd, NULL, TRUE);
        }
        return 0;
    case WM_PAINT:
        hDC = BeginPaint(hWnd, &ps);

        for(i = 0; i < NUMLINES; i++)
        {
            y = cyChar * (i - iVscrollPos);
            TextOut(hDC, 0, y, sysmetrics[i].szLabel, lstrlen(sysmetrics[i].szLabel));

            TextOut(hDC, 22 * cxChar, y, sysmetrics[i].szDesc, lstrlen(sysmetrics[i].szDesc));
            SetTextAlign(hDC, TA_RIGHT| TA_TOP);
            TextOut(hDC, 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, nMsg, wParam, lParam);
}

BOOL RegisterWnd(LPSTR pszClassName)
{
    WNDCLASSEX wce = {0};
    wce.cbSize = sizeof(wce);
    wce.cbClsExtra = 0;
    wce.cbWndExtra = 0;
    wce.hbrBackground = HBRUSH(COLOR_WINDOW);
    wce.lpfnWndProc = ParentProc;
    wce.hCursor = NULL;
    wce.hIcon = NULL;
    wce.hIconSm = NULL;
    wce.hInstance = g_hInst;
    wce.lpszClassName = pszClassName;
    wce.lpszMenuName = NULL;
    wce.style = CS_HREDRAW | CS_VREDRAW;

    ATOM nAtom = RegisterClassEx(&wce);
    if(0 == nAtom)
    {
        return FALSE;
    }

    return TRUE;
}

HWND CreateWnd(LPSTR pszClassName)
{
    HWND hWnd = CreateWindowEx(
                0,pszClassName,"窗口",WS_OVERLAPPEDWINDOW | WS_VSCROLL ,CW_USEDEFAULT,
                CW_USEDEFAULT, CW_USEDEFAULT,CW_USEDEFAULT,NULL,NULL,g_hInst,NULL);

    return hWnd;
}

void DisplayWnd(HWND hWnd)
{
    ShowWindow(hWnd,SW_SHOW);
    UpdateWindow(hWnd);
}

void Message()
{
    MSG msg = {0};
    while(GetMessage(&msg,NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
}

int WINAPI WinMain(HINSTANCE hInstance,
                    HINSTANCE hPrevInstance,
                    LPSTR pszCmdLine,
                    int nShowCmd)
{
    g_hInst = hInstance;
    RegisterWnd("MYWND");
    HWND hWnd = CreateWnd("MYWND");
    DisplayWnd(hWnd);
    Message();
    return 0;
}