JavaScript 时间戳与日期格式互转及 Date 对象用法详解

function timestampToTime(timestamp) {
  // 时间戳为10位需*1000，时间戳为13位不需乘1000
  var date = new Date(timestamp * 1000);
  var Y = date.getFullYear() + "-";
  var M =
    (date.getMonth() + 1 < 10
      ? "0" + (date.getMonth() + 1)
      : date.getMonth() + 1) + "-";
  var D = (date.getDate() < 10 ? "0" + date.getDate() : date.getDate()) + " ";
  var h = date.getHours() + ":";
  var m = date.getMinutes() + ":";
  var s = date.getSeconds();
  return Y + M + D + h + m + s;
}
console.log(timestampToTime(1670145353)); //2022-12-04 17:15:53

var date = new Date("2022-12-04 17:15:53:555");
// 有三种方式获取
var time1 = date.getTime();
var time2 = date.valueOf();
var time3 = Date.parse(date);
console.log(time1); //1670145353555
console.log(time2); //1670145353555
console.log(time3); //1670145353000

var now = new Date();
now;
now.getFullYear(); // 2021, 年份
now.getMonth(); // 2, 月份，月份范围是0~11，2表示3月
now.getDate(); //  4, 表示4号
now.getDay(); // 3, 星期三
now.getHours(); // 16, 表示19h
now.getMinutes(); // 41, 分钟
now.getSeconds(); // 22, 秒
now.getMilliseconds(); // 473, 毫秒数
now.getTime(); // 1614847074473, 以number形式表示的时间戳

var d = new Date(2021, 3, 4, 16, 15, 30, 123);

var d = Date.parse('2021-03-04 16:49:22.123');
d; // 1614847762123
// 尝试更多方式
(new Date()).valueOf(); 
new Date().getTime(); 
Number(new Date()); 

var d = Date.parse('2021-03-04 16:49:22.123');
d; // 1614847762123
// 尝试更多方式
(new Date()).valueOf(); 
new Date().getTime(); 
Number(new Date()); 

function getDate() {
    var now = new Date(),
        y = now.getFullYear(),
        m = now.getMonth() + 1,
        d = now.getDate();
    return y + "-" + (m < 10 ? "0" + m : m) + "-" + (d < 10 ? "0" + d : d) + " " + now.toTimeString().substr(0, 8);
}
getDate() // "2021-03-04 16:56:39"