如何以12小时格式(AM/PM)显示JavaScript datetime对象?


当前回答

下面是解决方案

var d = new Date();
var amOrPm = (d.getHours() < 12) ? "AM" : "PM";
var hour = (d.getHours() < 12) ? d.getHours() : d.getHours() - 12;
return   d.getDate() + ' / ' + d.getMonth() + ' / ' + d.getFullYear() + ' ' + hour + ':' + d.getMinutes() + ' ' + amOrPm;

其他回答

我的建议是使用moment js进行日期和时间操作。

https://momentjs.com/docs/#/displaying/format/

console.log(时刻)。格式(“hh: mm ')); < script src = " / / cdnjs.cloudflare.com/ajax/libs/moment.js/2.17.1/moment.min.js " > < /脚本>

如果你不需要打印上午/下午,我发现以下内容很好很简洁:

var now = new Date();
var hours = now.getHours() % 12 || 12;  // 12h instead of 24h, with 12 instead of 0. 

这是基于@bbrame的回答。

希望这个答案比其他答案更容易理解(尤其是对新手来说)。

以下是我在一些站点中实现的解决方案,用于通知上次修改站点代码的时间。它通过date的选项参数实现AM/PM时间。toLocaleDateString(参见相关的Mozilla文档)。

// Last time page code was updated/changed
const options = {
    year: "numeric",
    month: "long",
    weekday: "long",
    day: "numeric",
    hour: "numeric",
    minute: "numeric",
    second: "numeric",
    hour12: true // This is the line of code we care about here
    /*
        false: displays 24hs format for time
        true: displays 12, AM and PM format
    */
};

let last = document.lastModified;
let date = new Date(last);
let local = date.toLocaleDateString("en-US", options);
let fullDate = `${local}`;
document.getElementById("updated").textContent = fullDate;

输出的格式是:

Saturday, May 28, 2022, 8:38:50 PM

该输出然后显示在以下HTML代码中:

<p>Last update: <span id="updated">_update_date_goes_here</span></p>

注意:在这个用例中,是文档。lastModified有一些奇怪的行为,这取决于它是在本地运行还是在外部服务器上运行(参见这个堆栈溢出问题)。虽然当我在我的GitHub页面上运行它时,它可以正常工作(你应该在网站的页脚处看到它在运行)。

这里有另一种简单有效的方法:

        var d = new Date();

        var weekday = new Array(7);
        weekday[0] = "Sunday";
        weekday[1] = "Monday";
        weekday[2] = "Tuesday";
        weekday[3] = "Wednesday";
        weekday[4] = "Thursday";
        weekday[5] = "Friday";
        weekday[6] = "Saturday";

        var month = new Array(11);
        month[0] = "January";
        month[1] = "February";
        month[2] = "March";
        month[3] = "April";
        month[4] = "May";
        month[5] = "June";
        month[6] = "July";
        month[7] = "August";
        month[8] = "September";
        month[9] = "October";
        month[10] = "November";
        month[11] = "December";

        var t = d.toLocaleTimeString().replace(/:\d+ /, ' ');

        document.write(weekday[d.getDay()] + ',' + " " + month[d.getMonth()] + " " + d.getDate() + ',' + " " + d.getFullYear() + '<br>' + d.toLocaleTimeString());

    </script></div><!-- #time -->

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