sicily 7618. 9.5 The Time class

Description

Design a class name Time. The class contains:

Data field hour, minute, and second that represent a time.

A no-arg constructor that creates a Time object for the current time. (The data fields value will represent the current time.)

A constructor that constructs a Time object with a specified elapsetime since the middle of night, Jan 1, 1970 in seconds. (The data fields value will represent the current time.)

Three get functions from the data fields hour, minute, and second, respectively.

class Time
{
  public:
    Time();
    Time(int totalSeconds);
    int getHour();
    int getMinute();
    int getSecond();
};

Hint

只提交Time类实现，不要提交main()函数。

 

又来挖其他班的作业做了……第一次接触到时间库函数（time.h），查了不少资料。

NOTE:数据类型time_t和long其实是同义词，time(NULL)可以返回距离1970年1月1日的秒数（time_t类型），向localtime函数传入这样的秒数（注意要传time_t类型的指针）会返回一个存储有各类时间信息的tm结构体指针，其中的tm_hour、tm_min等就是依据给出的秒数换算出的当时的时分秒，结构体里的其他成员信息可以去文档里看。

自己测试了一下，创建一个用默认值的对象可以正常显示出当前时间

#include<time.h>
#include<iostream>
using namespace std;
class Time
{
    public:
        Time();
        Time( int totalSeconds );
        int getHour();
        int getMinute();
        int getSecond();
    private:
        int hour;
        int minute;
        int second;
};

Time::Time()
{
    time_t timer = time( NULL );
    struct tm *tblock = localtime( &timer );
    
    hour = tblock->tm_hour;
    minute = tblock->tm_min;
    second = tblock->tm_sec;
}

Time::Time( int totalSeconds )
{
    time_t timer = (time_t)totalSeconds;
    struct tm *tblock = localtime( &timer );
    
    hour = tblock->tm_hour;
    minute = tblock->tm_min;
    second = tblock->tm_sec;
}

int Time::getHour()
{
    return hour;
}

int Time::getMinute()
{
    return minute;
}
int Time::getSecond()
{
    return second;
}