更新以获得更多压缩

const formatAMPM = (date) => {
  let hours = date.getHours();
  let minutes = date.getMinutes();    
  const ampm = hours >= 12 ? 'pm' : 'am';

  hours %= 12;
  hours = hours || 12;    
  minutes = minutes < 10 ? `0${minutes}` : minutes;

  const strTime = `${hours}:${minutes} ${ampm}`;

  return strTime;
};

console.log(formatAMPM(new Date()));

更新以获得更多压缩

const formatAMPM = (date) => {
  let hours = date.getHours();
  let minutes = date.getMinutes();    
  const ampm = hours >= 12 ? 'pm' : 'am';

  hours %= 12;
  hours = hours || 12;    
  minutes = minutes < 10 ? `0${minutes}` : minutes;

  const strTime = `${hours}:${minutes} ${ampm}`;

  return strTime;
};

console.log(formatAMPM(new Date()));

   const formatAMPM = (date) => {
    try {
      let time = date.split(" ");
      let hours = time[4].split(":")[0];
      let minutes = time[4].split(":")[1];
      hours = hours || 12;
      const ampm = hours >= 12 ? " PM" : " AM";
      minutes = minutes < 10 ? `${minutes}` : minutes;
      hours %= 12;
      const strTime = `${hours}:${minutes} ${ampm}`;
      return strTime;
    } catch (e) {
      return "";
    }
  };

const startTime = "2021-12-07T17:00:00.073Z"
formatAMPM(new Date(startTime).toUTCString())

一个简短而甜蜜的实现:

// returns date object in 12hr (AM/PM) format
var formatAMPM = function formatAMPM(d) {
    var h = d.getHours();
    return (h % 12 || 12)
        + ':' + d.getMinutes().toString().padStart(2, '0')
        + ' ' + (h < 12 ? 'A' : 'P') + 'M';
};

使用dateObj。toLocaleString([地区[选项]])

选项1 -使用区域设置

var date = new Date();
console.log(date.toLocaleString('en-US'));

选项2 -使用选项

var options = { hour12: true };
console.log(date.toLocaleString('en-GB', options));

注:支持除safari atm以外的所有浏览器

使用Moment.js

使用moment.js时，请在JavaScript中使用以下代码

H, HH       24 hour time
h, or hh    12 hour time (use in conjunction with a or A)

format()方法以特定格式返回日期。

moment(new Date()).format("YYYY-MM-DD HH:mm"); // 24H clock
moment(new Date()).format("YYYY-MM-DD hh:mm A"); // 12H clock (AM/PM)
moment(new Date()).format("YYYY-MM-DD hh:mm a"); // 12H clock (am/pm)