javascript - 在javascript中如何更改以下日期格式

Question

我的日期格式是 181221171403

18-year
12-month
21-day
17-hour
14-minute
03-second

如何转换以下格式。

December 21st 2018, 17:14:03.000

Answer 1

var str = '181221171403';
var dateArr = str.match(/.{1,2}/g); // given ["18", "12", "21", "17", "14", "03"]
var strDate = '20'+dateArr[0]+'-'+dateArr[1]+'-'+dateArr[2]+' '+dateArr[3]+':'+dateArr[4]+':'+dateArr[5];
var d = new Date(strDate);

const monthNames = ["January", "February", "March", "April", "May", "June",
  "July", "August", "September", "October", "November", "December"
];

// December 21st 2018, 17:14:03.000
const res = monthNames[d.getMonth()]+' '+d.getDate()+' '+d.getFullYear()+' '+d.getFullYear()+' '+d.getHours()+':'+d.getMinutes()+':'+d.getSeconds()+'.000';
console.log(res);

然后你可以使用 JavaScript 的 objectv Date 生成格式为 shouaite 的日期