小程序格式化时间戳代码段

//formatTime.js
function formatTime(timestamp, format) {
  const formateArr = ['Y', 'M', 'D', 'h', 'm', 's'];
  let returnArr = [];
  let date = new Date(timestamp); //13位的时间戳,    如果不是13位的,  就要乘1000,就像这样 let date = new Date(timestamp*1000)
  let year = date.getFullYear()
  let month = date.getMonth() + 1
  let day = date.getDate()
  let hour = date.getHours()
  let minute = date.getMinutes()
  let second = date.getSeconds()
  returnArr.push(year, month, day, hour, minute, second);
  returnArr = returnArr.map(formatNumber);
  for (var i in returnArr) {
    format = format.replace(formateArr[i], returnArr[i]);
  }
  return format;
}
const formatNumber = n => {
  n = n.toString()
  return n[1] ? n : '0' + n
}

module.exports = {
  formatTime: formatTime
}

//引入formatTime.js
const time = require('formatTime.js');

//毫秒级的时间戳
var timestamp=1550665421000;
console.log('timestamp:', time.formatTime(timestamp, 'Y-M-D'));
console.log('timestamp:', time.formatTime(timestamp, 'Y:M:D'));

//输出为
timestamp: 2019-2-20
timestamp: 2019:2:20