Windows程序设计-定时器

应用

计时程序
多任务
维护更新过的状态报，实时更新
自动储存
终止程序展示版本的执行
步进移动
多媒体

三种方法

方法一

SetTimer (hwnd, 1, uiMsecInterval, NULL) ;

第一个参数是其窗口消息处理程序将接收WM_TIMER消息的窗口句柄。第二个参数是定时器ID，它是一个非0数值，在整个例子中假定为1。第三个参数是一个32位无正负号整数，以毫秒为单位指定一个时间间隔，一个60,000的值将使Windows每分钟发送一次WM_TIMER消息。

停止WM_TIMER消息：

KillTimer (hwnd, 1) ;

此函数的第二个参数是SetTimer呼叫中所用的同一个定时器ID。在终止程序之前，您应该响应WM_DESTROY消息停止任何活动的定时器。

方法二：回调函数

SetTimer (hwnd, iTimerID, iMsecInterval, TimerProc) ;

方法三

设定定时器的第三种方法类似于第二种方法，只是传递给SetTimer的hwnd参数被设定为NULL，并且第二个参数（通常为定时器ID）被忽略了，最后，此函数传回定时器ID。

iTimerID = SetTimer (NULL, 0, wMsecInterval, TimerProc) ;

KillTimer (NULL, iTimerID) ;

定时器用于时钟

digclock

/*----------------------------------------------------------------------------
DIGCLOCK.C -- Digital Clock
(c) Charles Petzold, 1998
----------------------------------------------------------------------------*/
#include <windows.h>
#define ID_TIMER 1
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    PSTR szCmdLine, int
    iCmdShow)
{
    static TCHAR szAppName[] = TEXT("DigClock");
    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("Program requires Windows NT!"),
            szAppName, MB_ICONERROR);
        return 0;
    }
    hwnd = CreateWindow(szAppName, TEXT("Digital Clock"),
        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;
}
void DisplayDigit(HDC hdc, int iNumber)
{
    static BOOL fSevenSegment[10][7] = {
        1, 1, 1, 0, 1, 1, 1, // 0
        0, 0, 1, 0, 0, 1, 0, // 1
        1, 0, 1, 1, 1, 0, 1, // 2
        1, 0, 1, 1, 0, 1, 1, // 3
        0, 1, 1, 1, 0, 1, 0, // 4
        1, 1, 0, 1, 0, 1, 1, // 5
        1, 1, 0, 1, 1, 1, 1, // 6
        1, 0, 1, 0, 0, 1, 0, // 7
        1, 1, 1, 1, 1, 1, 1, // 8
        1, 1, 1, 1, 0, 1, 1 }; // 9
    static POINT ptSegment[7][6] = {
        7, 6, 11, 2, 31, 2, 35, 6, 31, 10, 11,
        10,
        6, 7, 10, 11, 10, 31, 6, 35, 2, 31, 2, 11,
        36, 7, 40, 11, 40, 31, 36, 35, 32, 31, 32, 11,
        7, 36, 11, 32, 31, 32, 35, 36, 31, 40, 11, 40,
        6, 37, 10, 41, 10, 61, 6, 65, 2, 61, 2, 41,
        36, 37, 40, 41, 40, 61, 36, 65, 32, 61, 32, 41,
        7, 66, 11, 62, 31, 62, 35, 66, 31, 70, 11, 70 };
    int iSeg;
    for (iSeg = 0; iSeg < 7; iSeg++)
    if (fSevenSegment[iNumber][iSeg])
        Polygon(hdc, ptSegment[iSeg], 6);
}
void DisplayTwoDigits(HDC hdc, int iNumber, BOOL fSuppress)
{
    if (!fSuppress || (iNumber / 10 != 0))
        DisplayDigit(hdc, iNumber / 10);
    OffsetWindowOrgEx(hdc, -42, 0, NULL);
    DisplayDigit(hdc, iNumber % 10);
    OffsetWindowOrgEx(hdc, -42, 0, NULL);
}
void DisplayColon(HDC hdc)
{
    POINT ptColon[2][4] = { 2, 21, 6, 17, 10, 21,
        6, 25,
        2, 51, 6, 47, 10, 51, 6,
        55 };
    Polygon(hdc, ptColon[0], 4);
    Polygon(hdc, ptColon[1], 4);
    OffsetWindowOrgEx(hdc, -12, 0, NULL);
}
void DisplayTime(HDC hdc, BOOL f24Hour, BOOL fSuppress)
{
    SYSTEMTIME st;
    GetLocalTime(&st);
    if (f24Hour)
        DisplayTwoDigits(hdc, st.wHour, fSuppress);
    else
        DisplayTwoDigits(hdc, (st.wHour %= 12) ? st.wHour : 12, fSuppress);
    DisplayColon(hdc);
    DisplayTwoDigits(hdc, st.wMinute, FALSE);
    DisplayColon(hdc);
    DisplayTwoDigits(hdc, st.wSecond, FALSE);
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM
    wParam, LPARAM lParam)
{
    static BOOL f24Hour, fSuppress;
    static HBRUSH hBrushRed;
    static int cxClient, cyClient;
    HDC hdc;
    PAINTSTRUCT ps;
    TCHAR szBuffer[2];
    switch (message)
    {
    case WM_CREATE:
        hBrushRed = CreateSolidBrush(RGB(255, 0, 0));
        SetTimer(hwnd, ID_TIMER, 1000, NULL);// fall through
    case WM_SETTINGCHANGE:
        GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_ITIME, szBuffer,
            2);
        f24Hour = (szBuffer[0] == '1');
        GetLocaleInfo(LOCALE_USER_DEFAULT, LOCALE_ITLZERO,
            szBuffer, 2);
        fSuppress = (szBuffer[0] == '0');
        InvalidateRect(hwnd, NULL, TRUE);
        return 0;
    case WM_SIZE:
        cxClient = LOWORD(lParam);
        cyClient = HIWORD(lParam);
        return 0;
    case WM_TIMER:
        InvalidateRect(hwnd, NULL, TRUE);
        return 0;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        SetMapMode(hdc, MM_ISOTROPIC);
        SetWindowExtEx(hdc, 276, 72, NULL);
        SetViewportExtEx(hdc, cxClient, cyClient, NULL);
        SetWindowOrgEx(hdc, 138, 36, NULL);
        SetViewportOrgEx(hdc, cxClient / 2, cyClient / 2, NULL);
        SelectObject(hdc, GetStockObject(NULL_PEN));
        SelectObject(hdc, hBrushRed);
        DisplayTime(hdc, f24Hour, fSuppress);
        EndPaint(hwnd, &ps);
        return 0;
    case WM_DESTROY:
        KillTimer(hwnd, ID_TIMER);
        DeleteObject(hBrushRed);
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, message, wParam, lParam);
}

调用Windows函数GetLocalTime返回SYSTEMTIME格式的当地时间。

SYSTEMTIME st ;
GetLocalTime (&st) ;

在WINBASE.H中定义为：

typedef struct _SYSTEMTIME
{
WORD wYear ;
WORD wMonth ;
WORD wDayOfWeek ;
WORD wDay ;
WORD wHour ;
WORD wMinute ;
WORD wSecond ;
WORD wMilliseconds ;
}
SYSTEMTIME, * PSYSTEMTIME ;

模拟时钟

clock

/*---------------------------------------------------------------------------
CLOCK.C -- Analog Clock Program
(c) Charles Petzold, 1998
---------------------------------------------------------------------------*/
#include <windows.h>
#include <math.h>
#define ID_TIMER 1
#define TWOPI (2 * 3.14159)
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    PSTR
    szCmdLine, int iCmdShow)
{
    static TCHAR szAppName[] = TEXT("Clock");
    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 = NULL;
    wndclass.hCursor = LoadCursor(NULL,
        IDC_ARROW);
    wndclass.hbrBackground = (HBRUSH)
        GetStockObject(WHITE_BRUSH);
    wndclass.lpszMenuName = NULL;
    wndclass.lpszClassName = szAppName;
    if (!RegisterClass(&wndclass))
    {
        MessageBox(NULL, TEXT("Program requires Windows NT!"),
            szAppName, MB_ICONERROR);
        return 0;
    }
    hwnd = CreateWindow(szAppName, TEXT("Analog Clock"),
        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;
}
void SetIsotropic(HDC hdc, int cxClient, int cyClient)
{
    SetMapMode(hdc, MM_ISOTROPIC);
    SetWindowExtEx(hdc, 1000, 1000, NULL);
    SetViewportExtEx(hdc, cxClient / 2, -cyClient / 2, NULL);
    SetViewportOrgEx(hdc, cxClient / 2, cyClient / 2, NULL);
}
void RotatePoint(POINT pt[], int iNum, int iAngle)
{
    int i;
    POINT ptTemp;
    for (i = 0; i < iNum; i++)
    {
        ptTemp.x = (int)(pt[i].x * cos(TWOPI * iAngle / 360) +
            pt[i].y * sin(TWOPI * iAngle / 360));
        ptTemp.y = (int)(pt[i].y * cos(TWOPI * iAngle / 360) -
            pt[i].x * sin(TWOPI * iAngle / 360));
        pt[i] = ptTemp;
    }
}
void DrawClock(HDC hdc)
{
    int iAngle;
    POINT pt[3];
    for (iAngle = 0; iAngle < 360; iAngle += 6)
    {
        pt[0].x = 0;
        pt[0].y = 900;
        RotatePoint(pt, 1, iAngle);
        pt[2].x = pt[2].y = iAngle % 5 ? 33 : 100;
        pt[0].x -= pt[2].x / 2;
        pt[0].y -= pt[2].y / 2;
        pt[1].x = pt[0].x + pt[2].x;
        pt[1].y = pt[0].y + pt[2].y;
        SelectObject(hdc, GetStockObject(BLACK_BRUSH));
        Ellipse(hdc, pt[0].x, pt[0].y, pt[1].x, pt[1].y);
    }
}
void DrawHands(HDC hdc, SYSTEMTIME * pst, BOOL fChange)
{
    static POINT pt[3][5] = { 0, -150, 100, 0, 0, 600, -100, 0, 0, -150,
        0, -200, 50, 0, 0, 800, -50, 0, 0, -200,
        0, 0, 0, 0, 0, 0, 0, 0, 0, 800 };
    int i, iAngle[3];
    POINT ptTemp[3][5];
    iAngle[0] = (pst->wHour * 30) % 360 + pst->wMinute / 2;
    iAngle[1] = pst->wMinute * 6;
    iAngle[2] = pst->wSecond * 6;
    memcpy(ptTemp, pt, sizeof (pt));
    for (i = fChange ? 0 : 2; i < 3; i++)
    {
        RotatePoint(ptTemp[i], 5, iAngle[i]);
        Polyline(hdc, ptTemp[i], 5);
    }
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM
    wParam, LPARAM lParam)
{
    static int cxClient, cyClient;
    static SYSTEMTIME stPrevious;
    BOOL fChange;
    HDC hdc;
    PAINTSTRUCT ps;
    SYSTEMTIME st;
    switch (message)
    {
    case WM_CREATE:
        SetTimer(hwnd, ID_TIMER, 1000, NULL);
        GetLocalTime(&st);
        stPrevious = st;
        return 0;
    case WM_SIZE:
        cxClient = LOWORD(lParam);
        cyClient = HIWORD(lParam);
        return 0;
    case WM_TIMER:
        GetLocalTime(&st);
        fChange = st.wHour != stPrevious.wHour ||
            st.wMinute  != stPrevious.wMinute;
        hdc = GetDC(hwnd);
        SetIsotropic(hdc, cxClient, cyClient);
        SelectObject(hdc, GetStockObject(WHITE_PEN));
        DrawHands(hdc, &stPrevious, fChange);
        SelectObject(hdc, GetStockObject(BLACK_PEN));
        DrawHands(hdc, &st, TRUE);
        ReleaseDC(hwnd, hdc);
        stPrevious = st;
        return 0;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        SetIsotropic(hdc, cxClient, cyClient);
        DrawClock(hdc);
        DrawHands(hdc, &stPrevious, TRUE);
        EndPaint(hwnd, &ps);
        return 0;
    case WM_DESTROY:
        KillTimer(hwnd, ID_TIMER);
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, message, wParam, lParam);
}

以定时器进行状态报告

GetPixel

/*--------------------------------------------------------------------------
WHATCLR.C -- Displays Color Under Cursor
(c) Charles Petzold, 1998
---------------------------------------------------------------------------*/
#include <windows.h>
#define ID_TIMER 1
void FindWindowSize(int *, int *);
LRESULT CALLBACK WndProc(HWND, UINT, WPARAM, LPARAM);
int WINAPI WinMain(HINSTANCE hInstance, HINSTANCE hPrevInstance,
    PSTR szCmdLine, int
    iCmdShow)
{
    static TCHAR szAppName[] = TEXT("WhatClr");
    HWND hwnd;
    int cxWindow, cyWindow;
    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;
    }
    FindWindowSize(&cxWindow, &cyWindow);
    hwnd = CreateWindow(szAppName, TEXT("What Color"),
        WS_OVERLAPPED | WS_CAPTION | WS_SYSMENU |
        WS_BORDER,
        CW_USEDEFAULT, CW_USEDEFAULT,
        cxWindow, cyWindow,
        NULL, NULL, hInstance, NULL);
    ShowWindow(hwnd, iCmdShow);
    UpdateWindow(hwnd);
    while (GetMessage(&msg, NULL, 0, 0))
    {
        TranslateMessage(&msg);
        DispatchMessage(&msg);
    }
    return msg.wParam;
}
void FindWindowSize(int * pcxWindow, int * pcyWindow)
{
    HDC hdcScreen;
    TEXTMETRIC tm;
    hdcScreen = CreateIC(TEXT("DISPLAY"), NULL, NULL, NULL);
    GetTextMetrics(hdcScreen, &tm);
    DeleteDC(hdcScreen);
    *pcxWindow = 2 * GetSystemMetrics(SM_CXBORDER) +
        12 * tm.tmAveCharWidth;
    *pcyWindow = 2 * GetSystemMetrics(SM_CYBORDER) +
        GetSystemMetrics(SM_CYCAPTION) +
        2 * tm.tmHeight;
}
LRESULT CALLBACK WndProc(HWND hwnd, UINT message, WPARAM
    wParam, LPARAM lParam)
{
    static COLORREF cr, crLast;
    static HDC hdcScreen;
    HDC hdc;
    PAINTSTRUCT ps;
    POINT pt;
    RECT rc;
    TCHAR szBuffer[16];
    switch (message)
    {
    case WM_CREATE:
        hdcScreen = CreateDC(TEXT("DISPLAY"), NULL, NULL,
            NULL);
        SetTimer(hwnd, ID_TIMER, 100, NULL);
        return 0;
    case WM_TIMER:
        GetCursorPos(&pt);
        cr = GetPixel(hdcScreen, pt.x, pt.y);
        SetPixel(hdcScreen, pt.x, pt.y, 0);
        if (cr != crLast)
        {
            crLast = cr;
            InvalidateRect(hwnd, NULL, FALSE);
        }
        return 0;
    case WM_PAINT:
        hdc = BeginPaint(hwnd, &ps);
        GetClientRect(hwnd, &rc);
        wsprintf(szBuffer, TEXT(" %02X %02X %02X "),
            GetRValue(cr), GetGValue(cr), GetBValue(cr));
        DrawText(hdc, szBuffer, -1, &rc,
            DT_SINGLELINE | DT_CENTER | DT_VCENTER);
        EndPaint(hwnd, &ps);
        return 0;
    case WM_DESTROY:
        DeleteDC(hdcScreen);
        KillTimer(hwnd, ID_TIMER);
        PostQuitMessage(0);
        return 0;
    }
    return DefWindowProc(hwnd, message, wParam, lParam);
}

来源：CSDN

作者：lilongsy

链接：https://blog.csdn.net/lilongsy/article/details/77922628

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