如何以12小时格式(AM/PM)显示JavaScript datetime对象?
当前回答
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} ${ampm}`;
return strTime;
} catch (e) {
return "";
}
};
const startTime = "2021-12-07T17:00:00.073Z"
formatAMPM(new Date(startTime).toUTCString())
其他回答
或者只是简单地执行以下代码:
<script>
time = function() {
var today = new Date();
var h = today.getHours();
var m = today.getMinutes();
var s = today.getSeconds();
m = checkTime(m);
s = checkTime(s);
document.getElementById('txt_clock').innerHTML = h + ":" + m + ":" + s;
var t = setTimeout(function(){time()}, 0);
}
time2 = function() {
var today = new Date();
var h = today.getHours();
var m = today.getMinutes();
var s = today.getSeconds();
m = checkTime(m);
s = checkTime(s);
if (h>12) {
document.getElementById('txt_clock_stan').innerHTML = h-12 + ":" + m + ":" + s;
}
var t = setTimeout(function(){time2()}, 0);
}
time3 = function() {
var today = new Date();
var h = today.getHours();
var m = today.getMinutes();
var s = today.getSeconds();
if (h>12) {
document.getElementById('hour_line').style.width = h-12 + 'em';
}
document.getElementById('minute_line').style.width = m + 'em';
document.getElementById('second_line').style.width = s + 'em';
var t = setTimeout(function(){time3()}, 0);
}
checkTime = function(i) {
if (i<10) {i = "0" + i}; // add zero in front of numbers < 10
return i;
}
</script>
下面是一种使用regex的方法:
console.log(新日期(“7/10/2013 20:12:34”).toLocaleTimeString () .replace (/ ((\ d) +: \ d {2}) (: \ [d] {2 })(.*)/, "$ 1美元3”)) console.log(新日期(“7/10/2013 01:12:34”).toLocaleTimeString () .replace (/ ((\ d) +: \ d {2}) (: \ [d] {2 })(.*)/, "$ 1美元3”))
这将创建3个匹配组:
([\d]+:[\d]{2}) -小时:分钟 (:[\d]{2}) -秒 (.*) -空格和时段(时段是AM/PM的正式名称)
然后显示第1组和第3组。
警告:toLocaleTimeString()可能会根据区域/位置表现不同。
这是最简单的方法,你可以实现这使用三元操作符,或者你也可以使用if else代替!
const d = new Date();
let hrs = d.getHours();
let m = d.getMinutes();
// Condition to add zero before minute
let min = m < 10 ? `0${m}` : m;
const currTime = hrs >= 12 ? `${hrs - 12}:${min} pm` : `${hrs}:${min} am`;
console.log(currTime);
函数startTime() { const today = new Date(); let h = today.getHours(); let m = today.getMinutes(); let s = today.getSeconds(); Var子午线= h >= 12 ?pm: am; H = H % 12; H = H ?H: 12; M = M < 10 ?“0”+ m: m; S = S < 10 ?“0”+ s: s; var strTime = h +“:”+ m +”:“+ s + " " +子午线; . getelementbyid(的时间)。innerText = strTime; setTimeout(开始时间,1000); } 开始时间(); < h1 id = '时间' > < / h1 >
这是我的解决方案
function getTime() {
var systemDate = new Date();
var hours = systemDate.getHours();
var minutes = systemDate.getMinutes();
var strampm;
if (hours >= 12) {
strampm= "PM";
} else {
strampm= "AM";
}
hours = hours % 12;
if (hours == 0) {
hours = 12;
}
_hours = checkTimeAddZero(hours);
_minutes = checkTimeAddZero(minutes);
console.log(_hours + ":" + _minutes + " " + strampm);
}
function checkTimeAddZero(i) {
if (i < 10) {
i = "0" + i
}
return i;
}