C++时间标准库时间time和系统时间的使用

1. C++标准库中的时间需要引用time.h，可以取的本地时间或者格林威治时间，只能精确到秒

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#include <iostream>

 

/*包含time头文件*/

#include <time.h>

 

 

using namespace std;

 

int main()

{

    //time_t是long类型，精确到秒，是当前时间和1970年1月1日零点时间的差

    const time_t t = time(NULL);

 

    cout<<"current time is "<<t<<endl;

 

    /*本地时间：日期，时间 年月日，星期，时分秒*/

    struct tm* current_time = localtime(&t);

    printf("current year is %d;current month is %d;current date of month is %d\r\n",

        1900 + current_time->tm_year,

        1 + current_time->tm_mon/*此month的范围为0-11*/,

        current_time->tm_mday);

 

    printf("current day of year is %d;current day in week is %d\r\n",

        current_time->tm_yday,/*当前日期是今年的第多少天[0,365] */

        current_time->tm_wday/*days since Sunday - [0,6] */);

 

    printf("time part %d:%d:%d \r\n",

        current_time->tm_hour,

        current_time->tm_min,

        current_time->tm_sec);

 

    printf("\t本地时间：%d-%d-%d %d:%d:%d\r\n",

        current_time->tm_year + 1900,

        current_time->tm_mon + 1,

        current_time->tm_mday,

        current_time->tm_hour,

        current_time->tm_min,

        current_time->tm_sec);

 

    /*格林威治时间*/

    struct tm* current_gmtime = gmtime(&t);

 

    printf("格林威治时间：%d-%d-%d %d:%d:%d\r\n",

        current_gmtime->tm_year + 1900,

        current_gmtime->tm_mon + 1,

        current_gmtime->tm_mday,

        current_gmtime->tm_hour,

        current_gmtime->tm_min,

        current_gmtime->tm_sec);

 

 

    system("pause");

    return 0;

}

2. 系统时间 SYSTEMTIME 使用时要引用windows.h，可以精确到毫秒级别

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#include <iostream>

#include <Windows.h>

 

 

int main(){

    //声明变量

    SYSTEMTIME sys_time;

 

    //将变量值设置为本地时间

    GetLocalTime( &sys_time );

 

    //输出时间

    printf( "%4d/%02d/%02d %02d:%02d:%02d.%03d 星期%1d\n",sys_time.wYear,

        sys_time.wMonth,

        sys_time.wDay,

        sys_time.wHour,

        sys_time.wMinute,

        sys_time.wSecond,

        sys_time.wMilliseconds,

        sys_time.wDayOfWeek);

 

    system("time");

 

    system("pause");

    return 0;

}