C++时间标准库时间time和系统时间的使用

#include <iostream>
#include <time.h>
#include <stdio.h>
#include <windows.h>

using namespace std;

int main()
{
printf("%s","[time函数]\n");
//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("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);

cout <<'\n'<<endl;
cout <<'\n'<<endl;

printf("%s","[系统时间]\n");

//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;
}