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


当前回答

我发现它在这里工作得很好。

var date_format = '12'; /* FORMAT CAN BE 12 hour (12) OR 24 hour (24)*/
 
 
var d       = new Date();
var hour    = d.getHours();  /* Returns the hour (from 0-23) */
var minutes     = d.getMinutes();  /* Returns the minutes (from 0-59) */
var result  = hour;
var ext     = '';
 
if(date_format == '12'){
    if(hour > 12){
        ext = 'PM';
        hour = (hour - 12);
        result = hour;

        if(hour < 10){
            result = "0" + hour;
        }else if(hour == 12){
            hour = "00";
            ext = 'AM';
        }
    }
    else if(hour < 12){
        result = ((hour < 10) ? "0" + hour : hour);
        ext = 'AM';
    }else if(hour == 12){
        ext = 'PM';
    }
}
 
if(minutes < 10){
    minutes = "0" + minutes; 
}
 
result = result + ":" + minutes + ' ' + ext; 
 
console.log(result);

这是活塞的例子

其他回答

var d = new Date(); var hours = d.getHours() % 12; hours = hours ? hours : 12; var test = ['Jan', 'Feb', 'Mar', 'Apr', 'May', 'Jun', 'Jul', 'Aug', 'Sep', 'Oct', 'Nov', 'Dec'][(d.getMonth() + 1)] + " " + ("00" + d.getDate()).slice(-2) + " " + d.getFullYear() + " " + ("00" + hours).slice(-2) + ":" + ("00" + d.getMinutes()).slice(-2) + ":" + ("00" + d.getSeconds()).slice(-2) + ' ' + (d.getHours() >= 12 ? 'PM' : 'AM'); document.getElementById("demo").innerHTML = test; <p id="demo" ></p>

在现代浏览器中,使用Intl。DateTimeFormat和强制12小时格式选项:

    let now = new Date();

    new Intl.DateTimeFormat('default',
        {
            hour12: true,
            hour: 'numeric',
            minute: 'numeric'
        }).format(now);

    // 6:30 AM

如果您添加更多选项,使用default将尊重浏览器的默认区域,但仍将输出12小时格式。

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>

function getDateTime() {
  var now = new Date();
  var year = now.getFullYear();
  var month = now.getMonth() + 1;
  var day = now.getDate();

  if (month.toString().length == 1) {
    month = '0' + month;
  }
  if (day.toString().length == 1) {
    day = '0' + day;
  }

  var hours = now.getHours();
  var minutes = now.getMinutes();
  var ampm = hours >= 12 ? 'pm' : 'am';
  hours = hours % 12;
  hours = hours ? hours : 12;
  minutes = minutes < 10 ? '0' + minutes : minutes;
  var timewithampm = hours + ':' + minutes + ' ' + ampm;

  var dateTime = monthNames[parseInt(month) - 1] + ' ' + day + ' ' + year + ' ' + timewithampm;
  return dateTime;
}

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。