在JavaScript中每X分钟生成一次数组(作为字符串)

Question

我试图Date在整个24小时内每隔X分钟创建一个时间阵列(字符串,而不是对象).例如,对于5分钟的间隔,阵列将是:

['12:00 AM', '12:05 AM', '12:10 AM', '12:15 AM', ..., '11:55 PM']

我的快速而肮脏的解决方案是使用3个嵌套for循环:

var times = []
  , periods = ['AM', 'PM']
  , hours = [12, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11]
  , prop = null
  , hour = null
  , min = null; 

for (prop in periods) {
  for (hour in hours) {
    for (min = 0; min < 60; min += 5) {
      times.push(('0' + hours[hour]).slice(-2) + ':' + ('0' + min).slice(-2) + " " + periods[prop]);
    }
  }
}

这会输出所需的结果,但我想知道是否有更优雅的解决方案.有没有办法做到这一点:

• 更具可读性
• 减少时间复杂

Answer 1

如果间隔仅以分钟[0-60]设置,则评估以下解决方案,无需创建日期对象并在单循环中:

var x = 5; //minutes interval
var times = []; // time array
var tt = 0; // start time
var ap = ['AM', 'PM']; // AM-PM

//loop to increment the time and push results in array
for (var i=0;tt<24*60; i++) {
  var hh = Math.floor(tt/60); // getting hours of day in 0-24 format
  var mm = (tt%60); // getting minutes of the hour in 0-55 format
  times[i] = ("0" + (hh % 12)).slice(-2) + ':' + ("0" + mm).slice(-2) + ap[Math.floor(hh/12)]; // pushing data in array in [00:00 - 12:00 AM/PM format]
  tt = tt + x;
}

console.log(times);

Answer 2

分配结果数组以避免推送,参数验证和区域设置细节的开销,尽管如此:

function generate_series(step) {
    var dt = new Date(1970, 0, 1, 0, 0, 0, 0),
        rc = [];
    while (dt.getDate() == 1) {
        rc.push(dt.toLocaleTimeString('en-US'));
        dt.setMinutes(dt.getMinutes() + step);
    }
    return rc;
}

这是一个小提琴https://jsfiddle.net/m1ruw1x6/35/

Answer 3

在Moment.js的帮助下,以下内容非常灵活.

此代码使用

• moment.duration
• moment.add

没有错误处理,所以你可以传入愚蠢的参数,但它得到了重点.:-D

该desiredStartTime参数需要hh:mm格式化时间.

该period参数接受任何moment.duration输入.

const timelineLabels = (desiredStartTime, interval, period) => {
  const periodsInADay = moment.duration(1, 'day').as(period);

  const timeLabels = [];
  const startTimeMoment = moment(desiredStartTime, 'hh:mm');
  for (let i = 0; i <= periodsInADay; i += interval) {
    startTimeMoment.add(i === 0 ? 0 : interval, period);
    timeLabels.push(startTimeMoment.format('hh:mm A'));
  }

  return timeLabels;
};

/* A few examples */
const theDiv = document.getElementById("times");
let content;

content = JSON.stringify(timelineLabels('18:00', 2, 'hours'))
theDiv.appendChild(document.createTextNode(content));
theDiv.appendChild(document.createElement("p"));

content = JSON.stringify(timelineLabels('06:00', 30, 'm'))
theDiv.appendChild(document.createTextNode(content));
theDiv.appendChild(document.createElement("p"));

content = JSON.stringify(timelineLabels('00:00', 5, 'minutes'))
theDiv.appendChild(document.createTextNode(content));
theDiv.appendChild(document.createElement("p"));

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.18.1/moment.js"></script>

<div id="times"></div>

Answer 4

如果您有权访问moment，则可以始终执行以下操作：

const locale = 'en'; // or whatever you want...
const hours = [];

moment.locale(locale);  // optional - can remove if you are only dealing with one locale

for(let hour = 0; hour < 24; hour++) {
    hours.push(moment({ hour }).format('h:mm A'));
    hours.push(
        moment({
            hour,
            minute: 30
        }).format('h:mm A')
    );
}

结果是以下数组：

["12:00 AM", "12:30 AM", "1:00 AM", "1:30 AM", "2:00 AM", "2:30 AM", "3:00 AM", "3:30 AM", "4:00 AM", "4:30 AM", "5:00 AM", "5:30 AM", "6:00 AM", "6:30 AM", "7:00 AM", "7:30 AM", "8:00 AM", "8:30 AM", "9:00 AM", "9:30 AM", "10:00 AM", "10:30 AM", "11:00 AM", "11:30 AM", "12:00 PM", "12:30 PM", "1:00 PM", "1:30 PM", "2:00 PM", "2:30 PM", "3:00 PM", "3:30 PM", "4:00 PM", "4:30 PM", "5:00 PM", "5:30 PM", "6:00 PM", "6:30 PM", "7:00 PM", "7:30 PM", "8:00 PM", "8:30 PM", "9:00 PM", "9:30 PM", "10:00 PM", "10:30 PM", "11:00 PM", "11:30 PM"]

Answer 5

你只需要一个循环,遵循这种方法

var d = new Date(); //get a date object
d.setHours(0,0,0,0); //reassign it to today's midnight

现在继续添加5分钟,直到d.getDate()值发生变化

var date = d.getDate();
var timeArr = [];
while ( date == d.getDate() )
{
   var hours = d.getHours();
   var minutes = d.getMinutes();
   hours = hours == 0 ? 12: hours; //if it is 0, then make it 12
   var ampm = "am";
   ampm = hours > 12 ? "pm": "am";
   hours = hours > 12 ? hours - 12: hours; //if more than 12, reduce 12 and set am/pm flag
   hours = ( "0" + hours ).slice(-2); //pad with 0
   minute = ( "0" + d.getMinutes() ).slice(-2); //pad with 0
   timeArr.push( hours + ":" + minute + " " + ampm );
   d.setMinutes( d.getMinutes() + 5); //increment by 5 minutes
}

演示

Answer 6

此代码段根据区域设置生成范围，因此您无需手动处理 AM/PM。默认情况下，它将使用浏览器语言，但您可以传递用户选择的语言。

function getTimeRanges(interval, language = window.navigator.language) {
    const ranges = [];
    const date = new Date();
    const format = {
        hour: 'numeric',
        minute: 'numeric',
    };

    for (let minutes = 0; minutes < 24 * 60; minutes = minutes + interval) {
        date.setHours(0);
        date.setMinutes(minutes);
        ranges.push(date.toLocaleTimeString(language, format));
    }

    return ranges;
}

console.log('English', getTimeRanges(30, 'en'));
console.log('Russian', getTimeRanges(30, 'ru'));