将12小时时长: 毫米上午/下午转换为24小时时长: 毫米

试试这个

var time = $("#starttime").val();
var hours = Number(time.match(/^(\d+)/)[1]);
var minutes = Number(time.match(/:(\d+)/)[1]);
var AMPM = time.match(/\s(.*)$/)[1];
if(AMPM == "PM" && hours<12) hours = hours+12;
if(AMPM == "AM" && hours==12) hours = hours-12;
var sHours = hours.toString();
var sMinutes = minutes.toString();
if(hours<10) sHours = "0" + sHours;
if(minutes<10) sMinutes = "0" + sMinutes;
alert(sHours + ":" + sMinutes);

我必须做一些类似的事情，但是我正在生成一个 Date对象，所以我最终创建了一个这样的函数:

function convertTo24Hour(time) {
var hours = parseInt(time.substr(0, 2));
if(time.indexOf('am') != -1 && hours == 12) {
time = time.replace('12', '0');
}
if(time.indexOf('pm')  != -1 && hours < 12) {
time = time.replace(hours, (hours + 12));
}
return time.replace(/(am|pm)/, '');
}

我认为这样读起来会容易一些，您将字符串的格式设置为 h: mm am/pm。

    var time = convertTo24Hour($("#starttime").val().toLowerCase());
var date = new Date($("#startday").val() + ' ' + time);

例子:

        $("#startday").val('7/10/2013');


$("#starttime").val('12:00am');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 00:00:00 GMT-0700 (PDT)


$("#starttime").val('12:00pm');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 12:00:00 GMT-0700 (PDT)


$("#starttime").val('1:00am');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 01:00:00 GMT-0700 (PDT)


$("#starttime").val('12:12am');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 00:12:00 GMT-0700 (PDT)


$("#starttime").val('3:12am');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 03:12:00 GMT-0700 (PDT)


$("#starttime").val('9:12pm');
new Date($("#startday").val() + ' ' + convertTo24Hour($("#starttime").val().toLowerCase()));
Wed Jul 10 2013 21:12:00 GMT-0700 (PDT)

这里我的解决方案包括秒:

function convert_to_24h(time_str) {
// Convert a string like 10:05:23 PM to 24h format, returns like [22,5,23]
var time = time_str.match(/(\d+):(\d+):(\d+) (\w)/);
var hours = Number(time[1]);
var minutes = Number(time[2]);
var seconds = Number(time[3]);
var meridian = time[4].toLowerCase();


if (meridian == 'p' && hours < 12) {
hours += 12;
}
else if (meridian == 'a' && hours == 12) {
hours -= 12;
}
return [hours, minutes, seconds];
};

我已经创建了一个脚本@devnull69提交了一点改编。我觉得对于我的应用程序来说，它作为一个函数，返回我能够返回的值，然后作为一个变量使用，会更有用。

超文本标示语言

<input type="text" id="time_field" />
<button>Submit</submit>

JQuery

$(document).ready(function() {


function convertTime(time) {


var hours = Number(time.match(/^(\d\d?)/)[1]);
var minutes = Number(time.match(/:(\d\d?)/)[1]);
var AMPM = time.match(/\s(AM|PM)$/i)[1];


if((AMPM == 'PM' || AMPM == 'pm') && hours < 12) {
hours = hours + 12;
}
else if((AMPM == 'AM' || AMPM == "am") && hours == 12) {
hours = hours - 12;
}


var sHours = hours.toString();
var sMinutes = minutes.toString();


if(hours < 10) {
sHours = "0" + sHours;
}
else if(minutes < 10) {
sMinutes = "0" + sMinutes;
}


return sHours + ":" + sMinutes;


}


$('button').click(function() {
alert(convertTime($('#time_field').val()));
});


});

我需要这个功能的项目。我尝试了 devnull69，但遇到了一些麻烦，主要是因为字符串输入对 am/pm 部分非常特定，我需要更改验证。我把 Adrian P 的 jsfiddle 搞得一团糟，最终得到了一个似乎更适用于各种日期格式的版本。这是小提琴: http://jsfiddle.net/u91q8kmt/2/。

函数如下:

function ConvertTimeformat(format, str) {
var hours = Number(str.match(/^(\d+)/)[1]);
var minutes = Number(str.match(/:(\d+)/)[1]);
var AMPM = str.match(/\s?([AaPp][Mm]?)$/)[1];
var pm = ['P', 'p', 'PM', 'pM', 'pm', 'Pm'];
var am = ['A', 'a', 'AM', 'aM', 'am', 'Am'];
if (pm.indexOf(AMPM) >= 0 && hours < 12) hours = hours + 12;
if (am.indexOf(AMPM) >= 0 && hours == 12) hours = hours - 12;
var sHours = hours.toString();
var sMinutes = minutes.toString();
if (hours < 10) sHours = "0" + sHours;
if (minutes < 10) sMinutes = "0" + sMinutes;
if (format == '0000') {
return (sHours + sMinutes);
} else if (format == '00:00') {
return (sHours + ":" + sMinutes);
} else {
return false;
}
}

  function getDisplayDatetime() {
var d = new Date("February 04, 2011 19:00"),
hh = d.getHours(),  mm = d.getMinutes(),  dd = "AM", h = hh;
mm=(mm.toString().length == 1)? mm = "0" + mm:mm;
h=(h>=12)?hh-12:h;
dd=(hh>=12)?"PM":"AM";
h=(h == 0)?12:h;
var textvalue=document.getElementById("txt");
textvalue.value=h + ":" + mm + " " + dd;
}


</script>
</head>
<body>
<input type="button" value="click" onclick="getDisplayDatetime()">
<input type="text" id="txt"/>

这将有所帮助:

 function getTwentyFourHourTime(amPmString) {
var d = new Date("1/1/2013 " + amPmString);
return d.getHours() + ':' + d.getMinutes();
}

例如:

getTwentyFourHourTime("8:45 PM"); // "20:45"
getTwentyFourHourTime("8:45 AM"); // "8:45"

注意: 在“ Time”和“ am/pm”之间应该有一个用于时间字符串的空间。

有了这个，你可以得到以下东西: 输入样本: 07:05:45 PM 样本输出: < strong > 19:05:45

function timeConversion(s) {
let output = '';
const timeSeparator = ':'
const timeTokenType = s.substr(s.length - 2 , 2).toLowerCase();
const timeArr = s.split(timeSeparator).map((timeToken) => {
const isTimeTokenType =
timeToken.toLowerCase().indexOf('am') > 0 ||
timeToken.toLowerCase().indexOf('pm');
if(isTimeTokenType){
return timeToken.substr(0, 2);
} else {
return timeToken;
}
});
const hour = timeArr[0];
const minutes = timeArr[1];
const seconds = timeArr[2];
const hourIn24 = (timeTokenType === 'am') ? parseInt(hour) - 12 :
parseInt(hour) + 12;
return hourIn24.toString()+ timeSeparator + minutes + timeSeparator + seconds;
}

希望你喜欢！

对于将来阅读这篇文章的人来说，这里有一个更简单的答案:

var s = "11:41:02PM";
var time = s.match(/\d{2}/g);
if (time[0] === "12") time[0] = "00";
if (s.indexOf("PM") > -1) time[0] = parseInt(time[0])+12;
return time.join(":");

实时计算时间子午线的简单单一的 js 函数

JS

   function convertTime24to12(time24h) {
var timex = time24h.split(':');


if(timex[0] !== undefined && timex [1] !== undefined)
{
var hor = parseInt(timex[0]) > 12 ? (parseInt(timex[0])-12) : timex[0] ;
var minu = timex[1];
var merid = parseInt(timex[0]) < 12 ? 'AM' : 'PM';


var res = hor+':'+minu+' '+merid;


document.getElementById('timeMeridian').innerHTML=res.toString();
}
}

Html

 <label for="end-time">Hour <i id="timeMeridian"></i> </label>
<input type="time" name="hora" placeholder="Hora" id="end-time" class="form-control" onkeyup="convertTime24to12(this.value)">

基于@krzysztof-d Browski 的 回答的打字脚本解决方案

export interface HoursMinutes {
hours: number;
minutes: number;
}
export function convert12to24(time12h: string): HoursMinutes {
const [time, modifier] = time12h.split(' ');
let [hours, minutes] = time.split(':');


if (hours === '12') {
hours = '00';
}


if (minutes.length === 1) {
minutes = `0${minutes}`;
}


if (modifier.toUpperCase() === 'PM') {
hours = parseInt(hours, 10) + 12 + '';
}


return {
hours: parseInt(hours, 10),
minutes: parseInt(minutes, 10)
};
}

对所有用例进行了测试

function timeConversion(s) {
let h24;
let m24;
let sec24;


const splittedDate = s.split(":");
const h = parseInt(splittedDate[0], 10);
const m = parseInt(splittedDate[1], 10);
const sec = parseInt(splittedDate[2][0] + splittedDate[2][1], 10);
const meridiem = splittedDate[2][2] + splittedDate[2][3];


if (meridiem === "AM") {
if (h === 12) {
h24 = '00';
} else {
h24 = h;
if (h24 < 10) {
h24 = '0' + h24;
}
}
m24 = m;
sec24 = sec;
} else if (meridiem === "PM") {
if (h === 12) {
h24 = h
} else {
h24 = h + 12;
if (h24 < 10) {
h24 = '0' + h24;
}
}
m24 = m;
sec24 = sec;
}




if (m24 < 10) {
m24 = '0' + m24;
}


if (sec24 < 10) {
sec24 = '0' + sec24;
}


return h24 + ":" + m24 + ":" + sec24;
}

下面是 jsfiddle 的工作示例

计算时间为12小时到24小时的单行代码

任何格式的输入都可以正常工作

const convertTime12to24 = (time12h) => moment(time12h, 'hh:mm A').format('HH:mm');


console.log(convertTime12to24('06:30 pm'));


console.log(convertTime12to24('06:00 am'));


console.log(convertTime12to24('9:00 am'));


console.log(convertTime12to24('9pm')); 

<script src="https://cdnjs.cloudflare.com/ajax/libs/moment.js/2.29.1/moment.min.js"></script>

简短的 ES6代码

const convertFrom12To24Format = (time12) => {
const [sHours, minutes, period] = time12.match(/([0-9]{1,2}):([0-9]{2}) (AM|PM)/).slice(1);
const PM = period === 'PM';
const hours = (+sHours % 12) + (PM ? 12 : 0);


return `${('0' + hours).slice(-2)}:${minutes}`;
}

const convertFrom24To12Format = (time24) => {
const [sHours, minutes] = time24.match(/([0-9]{1,2}):([0-9]{2})/).slice(1);
const period = +sHours < 12 ? 'AM' : 'PM';
const hours = +sHours % 12 || 12;


return `${hours}:${minutes} ${period}`;
}

我刚刚在 HackerRank 上解决了这个问题，所以我在这里分享我的结果

function timeConversion(s) {
const isPM = s.indexOf('PM') !== -1;
let [hours, minutes, seconds] = s.replace(isPM ? 'PM':'AM', '').split(':');


if (isPM) {
hours = parseInt(hours, 10) + 12;
hours = hours === 24 ? 12 : hours;
} else {
hours = parseInt(hours, 10);
hours = hours === 12 ? 0 : hours;
if (String(hours).length === 1) hours = '0' + hours;
}


const time = [hours, minutes, seconds].join(':');


return time;
}

这适用于像 06:40:03AM这样的输入。

@ krzysztof 的扩展版本，可以按时工作，在时间和修饰符之间有或没有空格。

const convertTime12to24 = (time12h) => {
const [fullMatch, time, modifier] = time12h.match(/(\d?\d:\d\d)\s*(\w{2})/i);


let [hours, minutes] = time.split(':');


if (hours === '12') {
hours = '00';
}


if (modifier === 'PM') {
hours = parseInt(hours, 10) + 12;
}


return `${hours}:${minutes}`;
}


console.log(convertTime12to24('01:02 PM'));
console.log(convertTime12to24('05:06 PM'));
console.log(convertTime12to24('12:00 PM'));
console.log(convertTime12to24('12:00 AM'));

将 AM/PM 时间字符串转换为24小时格式。 例子9:30 PM 至21:30

function get24HrsFrmAMPM(timeStr) {
if (timeStr && timeStr.indexOf(' ') !== -1 && timeStr.indexOf(':') !== -1) {
var hrs = 0;
var tempAry = timeStr.split(' ');
var hrsMinAry = tempAry[0].split(':');
hrs = parseInt(hrsMinAry[0], 10);
if ((tempAry[1] == 'AM' || tempAry[1] == 'am') && hrs == 12) {
hrs = 0;
} else if ((tempAry[1] == 'PM' || tempAry[1] == 'pm') && hrs != 12) {
hrs += 12;
}
return ('0' + hrs).slice(-2) + ':' + ('0' + parseInt(hrsMinAry[1], 10)).slice(-2);
} else {
return null;
}
}

我就是这么做的:

function timeConversion(s) {
// Write your code here
const arr =s.split(":")
const isAM = arr[2].includes("AM")
if(isAM) {
arr[0]=arr[0].padStart(2, '0');
arr[2]=arr[2].replace("AM","");
if(arr[0]==="12")  arr[0] ="00"
           

}else{
arr[0]=(+arr[0]+12).toString();
arr[2]=arr[2].replace("PM","");
if(arr[0]==="24")  arr[0] ="12"
}
return(arr.join(":"))
}

我发现这是最简单的方法，下面是一步一步来说明正在发生的事情:

1. 时间是12小时

2. 按时间戳和子午线分割时间

3. 如果是午夜，则在 00之前打印时间戳

4. 如果是中午，只要打印时间戳，否则用 12添加小时

function timeConversion(s) {
// 07:05:45PM
const timeInAmPmArray = s.split(/(AM|PM)/) // ['07:05:45', 'PM', '']
const hour = Number(timeInAmPmArray[0].split(':')[0]) // 7
const amOrPm = timeInAmPmArray[1] // PM
let timeIn24Hour = ''
if(amOrPm === 'AM') {
timeIn24Hour = hour === 12 ? `00:${timeInAmPmArray[0].split(':').slice(1).join(':')}` : timeInAmPmArray[0]
} else {
timeIn24Hour = hour === 12 ? timeInAmPmArray[0] : `${hour + 12}:${timeInAmPmArray[0].split(':').slice(1).join(':')}`
// timeIn24Hour = 19:05:45
}
return timeIn24Hour
}
    

timeConversion('07:05:45PM')

这是一种蛮力解决方案，对我很有效

const time = '11:8AM';


function convertTo24HrsFormat(time) {
// write your solution here
let timeWithPM = time.endsWith("PM");
    

if (time.includes('P')) {
let minuteVal = time.slice(time.indexOf(':')+1, time.indexOf('P'));
      

if(minuteVal.length === 1) {
minuteVal = `0${minuteVal}`;
let result = time.slice(0, time.indexOf(':'));
time = `${result}:${minuteVal}PM`;
console.log("CHECKING123====>>>>", time);
}
}
    

if (time.includes('A')) {
let minuteVal = time.slice(time.indexOf(':')+1, time.indexOf('A'));
if(minuteVal.length === 1) {
minuteVal = `0${minuteVal}`;
let result = time.slice(0, time.indexOf(':'));
time = `${result}:${minuteVal}AM`;
}
}
        



if(timeWithPM) {
let result = findHour(time);
return result;
}


if(!timeWithPM) {
let result = withAM(time);
return result;
}


return;
}


function findHour(time) {
let hour = time.slice(0, time.indexOf(':'));
if(parseInt(hour) < 12)
hour = parseInt(hour)+12;
if (hour.toString().length === 1)
hour = `0${hour}`;
let removeHourWithPM = time.split(":").pop();
removeHourWithPM = `${hour}:${removeHourWithPM}`;
// console.log("CHECKING-----",hour);
return removeHourWithPM.slice(0, -2);
}


function withAM(time) {


let isTwelve = time.slice(0, time.indexOf(':'));
if(isTwelve == '12') {
let get12 = time.split(':').pop();
let result = get12.slice(0, -2);
return `00:${result}`
}
    

let hour = time.slice(0, time.indexOf(':'));
if(hour.length === 1) {
hour = `0${hour}`;
let removeHourWithSingledigit = time.split(":").pop();
removeHourWithSingledigit = `${hour}:${removeHourWithSingledigit}`;
return removeHourWithSingledigit.slice(0, -2);
}
    

return time.slice(0, -2);
}


console.log(`Converted time: ${convertTo24HrsFormat(time)}`)

function timeConversion(amPmStr = '') {
const time = amPmStr.replace(/(AM|PM|am|pm)/, (match) => ' ' + match);
const randomDate = "September 25, 2018 ";
const date = new Date(randomDate + time);
const hours = date.getHours().toString().padStart(2, '0');
const mins = date.getMinutes().toString().padStart(2, '0');
const secs = date.getSeconds().toString().padStart(2, '0');
return hours + ":" + mins + ":" + secs;
}

我加了一个简单的代码

const time = '12:10AM';


function convertTo24HrsFormat(time) {
let [hour, modifier] = time.split(":");
let min = parseInt(modifier).toString().padStart(2, '0');
let index = modifier.toLowerCase().indexOf('m');
let meridian = modifier.slice(index - 1);
hour = parseInt(hour);


if (hour === 12) {
hour = 00;
}


if (meridian == 'PM') {
hour = hour + 12;
}


hour = hour.toString().padStart(2, '0');




let time24hr = `${hour}:${min}`;


return time24hr;
}


console.log(`Converted time: ${convertTo24HrsFormat(time)}`);

一个经过检验的方法:

// example, s = 12:34:56PM
function timeConversion(s) {
let designator, clock, hhmmss, hh, mm, ss, mil; // declare variables
designator = s.slice(-2); // returns AM or PM
hhmmss = s.substring(0, s.length-2) // returns hh:mm:ss
clock = hhmmss.split(':'); // returns array of [hh,mm,ss]
hh = designator === 'AM'
? (parseInt(clock[0]) === 12 ? '00' : clock[0])
: (parseInt(clock[0]) === 12 ? '12' : parseInt(clock[0]) + 12);
mm = clock[1];
ss = clock[2];
mil = [hh,mm,ss].join(':').toString();
return mil

}

//here is my solution.
function timeConversion(s) {
// Write your code here
let amPM = s.indexOf('AM') !== -1 ? 'AM' : 'PM';
let tString = s.toString().replace(/AM|PM/gi,'');
let splitTime = tString.split(':');
let h = splitTime[0];
let m = splitTime[1];
let sec = splitTime[2];
let twntyfr = amPM === 'PM' && parseInt(h) !== 12 ? parseInt(h)+12 : h;
if(parseInt(twntyfr) === 12 && amPM === 'AM') twntyfr = '00';
return twntyfr+':'+m+':'+sec;
}

因为到目前为止所有的答案似乎都很冗长，这里有一个简单的极简主义解决方案:

/* Convert h:mm a/p to H:mm
* i.e. 12 hour time to 24 hour time
* @param {string} time - h:mm a/p format
* @returns {string} time in H:mm format
*/
function to24HrTime(time) {
let [hr, min, ap] = time.toLowerCase().match(/\d+|[a-z]+/g) || [];
return `${(hr % 12) + (ap == 'am'? 0 : 12)}:${min}`;
}


['9:02 am',
'9:02 pm',
'9:02am',
'9:02pm',
'12:15 AM',
'12:01 PM',
].forEach(time => console.log(`${time} -> ${to24HrTime(time)}`));

假设输入字符串具有合适的格式和值，更健壮的版本是:

/* Given 12 hr time, return24 hr time
* @param {string} time - time in format h:mm am/pm
*        h  must be in range 1 to 12
*        mm must be in range 00 to 59
*        am/pm is not case sensitive
* @returns {string} time in 24 hr format H:mm
*        H  in range 0 to 23
*        mm in range 00 to 59
*
*/
function to24HrTime(time = new Date().toLocaleString('en',{hour:'numeric', minute:'2-digit', hour12:true})) {
let [hr, min, ap] = String(time).toLowerCase().match(/\d+|[a-z]+/g) || [];
// If time is valid, return reformatted time
// Otherwise return undefined
return /^([1-9]|1[0-2]):[0-5]\d\s?(am|pm)/i.test(time)? `${(hr%12)+(ap=='am'?0:12)}:${min}` : void 0;
}


// Examples
// Without arguments
console.log(`No args -> ${to24HrTime()}`);
// Valid input
['9:02 am',
'9:02 pm',
'9:02am',
'9:02pm',
'12:15 AM',
'12:01 PM',
// Invalid input
'12',       // Missing mins & ap
'99:05 am', // hrs out of range
'0:05 am',  // hrs out of range
'9:60 am',  // mins out of range
'9:09 pp',  // ap out of range
{},         // Random object
].forEach(time => console.log(`${time} -> ${to24HrTime(time)}`));

HackerRank 时间转换解决方案

12小时上午/下午格式，军事(24小时)时间

function timeConversion(s) {
let time = 0
let hour = s.slice(0, 2)
let toD = s.slice(-2)


if (toD === 'AM' && hour == 12) {
time = `00${s.slice(2, s.length -2)}`
} else {
if (toD === 'PM' && hour < 12) {
time = `${Number(12 + parseInt(hour))}${s.slice(2, s.length - 2)}`
} else {
time = s.slice(0, s.length - 2)
}
}


return console.log(time)
}


timeConversion('12:00:17AM') // 00:00:17
timeConversion('09:21:33PM') // 21:21:33
timeConversion('12:43:53PM') // 12:43:53

下面是我的解决方案，使用正则表达式进行分割:

convert24To12(time){
let [hours, minutes, modifier] = time.split(/ |:/);
if (modifier === 'PM') {
hours = `${parseInt(hours, 10) + 12}`;
}
time = `${hours}:${minutes}`;
return time;
}