I am facing some issue while calculating the time difference between two dates using the JavaScript. I am providing my code below.
Here I have cutoff time and dep_time value. I have to calculate today's date with dep_date and if today's date and time is before the cutoff time then it will return true otherwise false. In my case its working fine in Chrome but for same function it's not working in Firefox. I need it to work for all browsers.
function checkform() {
var dep_date = $("#dep_date1").val(); //07/27/2019
var cut_offtime = $("#cutoff_time").val(); //1
var dep_time = $("#dep_time").val(); //6:00pm
var dep_time1 = dep_time.replace(/[ap]/, " $&");
var todayDate = new Date();
var todayMonth = todayDate.getMonth() + 1;
var todayDay = todayDate.getDate();
var todayYear = todayDate.getFullYear();
if (todayDay < 10) {
todayDay = "0" + todayDay;
}
if (todayMonth < 10) {
todayMonth = "0" + todayMonth;
}
//console.log('both dates',todayMonth,todayDay,todayYear);
var todayDateText = todayMonth + "-" + todayDay + "-" + todayYear;
var inputToDate = Date.parse(dep_date.replace(/\//g, " "));
var todayToDate = Date.parse(todayDateText.replace(/-/g, " "));
console.log("both dates", dep_date, todayDateText);
if (inputToDate >= todayToDate) {
var date = new Date();
var hours = date.getHours();
var minutes = date.getMinutes();
var ampm = hours >= 12 ? "pm" : "am";
hours = hours % 12;
hours = hours ? hours : 12; // the hour '0' should be '12'
minutes = minutes < 10 ? "0" + minutes : minutes;
var strTime = hours + ":" + minutes + " " + ampm;
var timeStart = new Date(todayDateText + " " + strTime);
var timeEnd = new Date(dep_date + " " + dep_time1);
var diff = (timeEnd - timeStart) / 60000; //dividing by seconds and milliseconds
var minutes = diff % 60;
var hours = (diff - minutes) / 60;
console.log("hr", hours);
if (parseInt(hours) > parseInt(cut_offtime)) {
return true;
} else {
alert("You should book this trip before " + cut_offtime + " hr");
return false;
}
} else {
alert("You should book this trip before " + cut_offtime + " hr");
return false;
}
}
Part of your issue is here:
var todayDateText = todayMonth + "-" + todayDay + "-" + todayYear;
var inputToDate = Date.parse(dep_date.replace(/\//g, " "));
The first line generates a string like "07-17-2019". The next changes it to "07 17 2019" and gives it to the built–in parser. That string is not a format supported by ECMA-262 so parsing is implementation dependent.
Chrome and Firefox return a date for 17 July 2019, Safari returns an invalid date.
It doesn't make sense to parse a string to get the values, then generate another string to be parsed by the built–in parser. Just give the first set of values directly to the Date constructor:
var inputToDate = new Date(todayYear, todayMonth - 1, todayDay);
which will work in every browser that ever supported ECMAScript.
Similarly:
var date = new Date();
var hours = date.getHours();
var minutes = date.getMinutes();
var ampm = hours >= 12 ? "pm" : "am";
hours = hours % 12;
hours = hours ? hours : 12; // the hour '0' should be '12'
minutes = minutes < 10 ? "0" + minutes : minutes;
var strTime = hours + ":" + minutes + " " + ampm;
var timeStart = new Date(todayDateText + " " + strTime);
appears to be a lengthy and brittle way to copy a date and set the seconds and milliseconds to zero. The following does exactly that in somewhat less code:
var date = new Date();
var timeStart = new Date(date);
timeStart.setMinutes(0,0);
use
var timeStart = new Date(todayDateText + " " + strTime)
Applying these changes to your code gives something like:
function parseMDY(s) {
var b = s.split(/\D/);
return new Date(b[2], b[0]-1, b[1]);
}
function formatDate(d) {
return d.toLocaleString(undefined, {
day: 'numeric',
month: 'short',
year: 'numeric'
});
}
// Call function with values
function checkform(dep_date, cut_offtime, dep_time) {
// Helper
function z(n) {
return (n<10?'0':'') + n;
}
// Convert dep_date to Date
var depD = parseMDY(dep_date);
// Get the departure time parts
var dtBits = dep_time.toLowerCase().match(/\d+|[a-z]+/gi);
var depHr = +dtBits[0] + (dtBits[2] == 'pm'? 12 : 0);
var depMin = +dtBits[1];
// Set the cutoff date and time
var cutD = new Date(depD);
cutD.setHours(depHr, depMin, 0, 0);
// Get current date and time
var now = new Date();
// Create cutoff string
var cutHr = cutD.getHours();
var cutAP = cutHr > 11? 'pm' : 'am';
cutHr = z(cutHr % 12 || 12);
cutMin = z(cutD.getMinutes());
var cutStr = cutHr + ':' + cutMin + ' ' + cutAP;
var cutDStr = formatDate(cutD);
// If before cutoff, OK
if (now < cutD) {
alert('Book before ' + cutStr + ' on ' + cutDStr);
return true;
// If after cutoff, not OK
} else {
alert('You should have booked before ' + cutStr + ' on ' + cutDStr);
return false;
}
}
// Samples
checkform('07/27/2019','1','6:00pm');
checkform('07/17/2019','1','11:00pm');
checkform('07/07/2019','1','6:00pm');
That refactors your code somewhat, but hopefully shows how to improve it and fix the parsing errors.
I'm basically trying to get the hours, minutes, and seconds of a date in javascript to read like this: '123456'. I am doing this with the following code:
var date;
date = new Date();
var time = date.getUTCHours() + date.getUTCMinutes() + date.getUTCSeconds();
Only problem is when I add them together, I keep getting the sum, not a nice line of 6 numbers like I want.
Any Suggestions?
var time = '' + date.getUTCHours() + date.getUTCMinutes() + date.getUTCSeconds();
edit:
To account for zero-padding you can do something like:
function format(x){
if (x < 10) return '0' + x;
return x;
}
var date;
date = new Date();
var time = '' + format(date.getUTCHours()) + format(date.getUTCMinutes()) + format(date.getUTCSeconds());
Convert the numerical value to a string:
var date;
date = new Date();
var time = date.getUTCHours().toString() + date.getUTCMinutes().toString() + date.getUTCSeconds().toString();
If you want it to always be 6 characters long, you need to pad the values if they are < 10. For example:
var hours = date.getUTCHours();
if (hours < 10)
hours = '0' + hours.toString();
else hours = hours.toString();
var mins = date.getUTCMinutes();
if (mins < 10)
mins = '0' + mins.toString();
else mins = mins.toString();
var secs = date.getUTCSeconds();
if (secs < 10)
secs = '0' + secs.toString();
else secs = secs.toString();
var time = hours + mins + secs;
That's happening because those functions return an Integer type. If you want to add the digits themself togheter, try converting every variable to string using toString()
I'm writing a shortcut JavaScript file to make $date and $time variables. It should work as far as I can tell, but it won't display and Google Chrome's debugger shows a [Uncaught TypeError: Cannot Read 'firstChild' of null]
Here's my code:
function mdy(){
var
h = new Date(),
year = h.getFullYear(),
month = h.getMonth() + 1,
day = h.getDate();
if(month < 10) { month = "0" + month; }
if(day < 10) { month = "0" + month; }
var string = month + "/" + day + "/" + year;
document.getElementById('mdy').firstChild.nodeValue = string;
}
function ymd(){
var
h = new Date(),
year = h.getFullYear(),
month = h.getMonth() + 1,
day = h.getDate();
if(month < 10) { month = "0" + month; }
if(day < 10) { month = "0" + month; }
var string = year + "/" + month + "/" + day;
document.getElementById('ymd').firstChild.nodeValue = string;
}
var $date = {
mdy: '<span id="mdy"> </span>',
ymd: '<span id="ymd"> </span>'
}
/* $time module */
// this comes in two formats, standard and military.
// type $time.standard for standard time and $time.military
// for military time
function tstandard(){
var
h = new Date(),
hours = h.getHours(),
minutes = h.getMinutes();
minutes = ( minutes < 10 ? "0" : "" ) + minutes;
var diem = ( hours < 12 ) ? "am" : "pm";
hours = ( hours > 12 ) ? hours - 12 : hours;
hours = ( hours == 0 ) ? 12 : hours;
var string = hours + ":" + minutes + " " + diem;
document.getElementById("tstandard").firstChild.nodeValue = string;
}
function tmilitary() {
var
h = new Date(),
hours = h.getHours(),
minutes = h.getMinutes();
minutes = ( minutes < 10 ? "0" : "" ) + minutes;
hours = ( hours == 0 ) ? 12 : hours;
if(hours < 10) { hours = "0" + hours }
var string = hours + ":" + minutes;
document.getElementById("tmilitary").firstChild.nodeValue = string;
}
var $time = {
standard: "<span id='tstandard'> </span>",
military: "<span id='tmilitary'> </span>"
}
/*! universal body onload function !*/
window.onload = function(){
mdy(); setInterval('mdy()', 1000);
ymd(); setInterval('ymd()', 1000);
tstandard(); setInterval('tstandard()', 1000);
tmilitary(); setInterval('tmilitary()', 1000);
}
And in my HTML, I'm doing:
<script>document.write($date.mdy + " - " + $time.standard);</script>
You are adding two placeholder elements to the DOM – <span id="ymd"></span> and <span id="tstandard">.
Then, in the window.onload handler, you are trying to update contents of not only these two placeholders but also of two other elements which are not in the DOM (id="ymd" and id="tmilitary"). The document.getElementById('ymd') (and 'tmilitary') call correctly returns undefined because of that fact.
You want to remove the calls to the ymd and tmilitary functions.
window.onload = function(){
mdy();
setInterval(mdy, 1000);
tstandard();
setInterval(tstandard, 1000);
};
I also changed the calls to setInterval to simplify things. Passing references is more efficient and clear.
I think you might want this:
document.getElementById('mdy').innerHTML = string;
or this:
document.getElementById('mdy').nodeValue = string;
instead of this:
document.getElementById('mdy').firstChild.nodeValue = string;
That should take care of the errors. (There's no need to get the firstChild from a getElementById call, it already returns a node by default.)
What is the best way to convert the following JSON returned value from a 24-hour format to 12-hour format w/ AM & PM? The date should stay the same - the time is the only thing that needs formatting.
February 04, 2011 19:00:00
P.S. Using jQuery if that makes it any easier! Would also prefer a simple function/code and not use Date.js.
This is how you can change hours without if statement:
hours = ((hours + 11) % 12 + 1);
UPDATE 2: without seconds option
UPDATE: AM after noon corrected, tested: http://jsfiddle.net/aorcsik/xbtjE/
I created this function to do this:
function formatDate(date) {
var d = new Date(date);
var hh = d.getHours();
var m = d.getMinutes();
var s = d.getSeconds();
var dd = "AM";
var h = hh;
if (h >= 12) {
h = hh - 12;
dd = "PM";
}
if (h == 0) {
h = 12;
}
m = m < 10 ? "0" + m : m;
s = s < 10 ? "0" + s : s;
/* if you want 2 digit hours:
h = h<10?"0"+h:h; */
var pattern = new RegExp("0?" + hh + ":" + m + ":" + s);
var replacement = h + ":" + m;
/* if you want to add seconds
replacement += ":"+s; */
replacement += " " + dd;
return date.replace(pattern, replacement);
}
alert(formatDate("February 04, 2011 12:00:00"));
//it is pm if hours from 12 onwards
suffix = (hours >= 12)? 'pm' : 'am';
//only -12 from hours if it is greater than 12 (if not back at mid night)
hours = (hours > 12)? hours -12 : hours;
//if 00 then it is 12 am
hours = (hours == '00')? 12 : hours;
For anyone reading who wants ONLY the time in the output, you can pass options to JavaScript's Date::toLocaleString() method. Example:
var date = new Date("February 04, 2011 19:00:00");
var options = {
hour: 'numeric',
minute: 'numeric',
hour12: true
};
var timeString = date.toLocaleString('en-US', options);
console.log(timeString);
timeString will be set to:
8:00 AM
Add "second: 'numeric'" to your options if you want seconds too. For all option see this.
Here's a reasonably terse way to do it using a Prototype:
Date.prototype.getFormattedTime = function () {
var hours = this.getHours() == 0 ? "12" : this.getHours() > 12 ? this.getHours() - 12 : this.getHours();
var minutes = (this.getMinutes() < 10 ? "0" : "") + this.getMinutes();
var ampm = this.getHours() < 12 ? "AM" : "PM";
var formattedTime = hours + ":" + minutes + " " + ampm;
return formattedTime;
}
Then all you have to do is convert your string value to a date and use the new method:
var stringValue = "February 04, 2011 19:00:00;
var dateValue = new Date(stringValue);
var formattedTime = dateValue.getFormattedTime();
Or in a single line:
var formattedTime = new Date("February 04, 2011 19:00:00").getFormattedTime();
Keep it simple and clean
var d = new Date();
var n = d.toLocaleString();
https://jsfiddle.net/rinu6200/3dkdxaad/#base
function pad(num) {return ("0" + num).slice(-2);}
function time1() {
var today = new Date(),
h = today.getHours(),
m = today.getMinutes(),
s = today.getSeconds();
h = h % 12;
h = h ? h : 12; // the hour '0' should be '12'
clk.innerHTML = h + ':' +
pad(m) + ':' +
pad(s) + ' ' +
(h >= 12 ? 'PM' : 'AM');
}
window.onload = function() {
var clk = document.getElementById('clk');
t = setInterval(time1, 500);
}
<span id="clk"></span>
jQuery doesn't have any Date utilities at all. If you don't use any additional libraries, the usual way is to create a JavaScript Date object and then extract the data from it and format it yourself.
For creating the Date object you can either make sure that your date string in the JSON is in a form that Date understands, which is IETF standard (which is basically RFC 822 section 5). So if you have the chance to change your JSON, that would be easiest. (EDIT: Your format may actually work the way it is.)
If you can't change your JSON, then you'll need to parse the string yourself and get day, mouth, year, hours, minutes and seconds as integers and create the Date object with that.
Once you have your Date object you'll need to extract the data you need and format it:
var myDate = new Date("4 Feb 2011, 19:00:00");
var hours = myDate.getHours();
var am = true;
if (hours > 12) {
am = false;
hours -= 12;
} else (hours == 12) {
am = false;
} else (hours == 0) {
hours = 12;
}
var minutes = myDate.getMinutes();
alert("It is " + hours + " " + (am ? "a.m." : "p.m.") + " and " + minutes + " minutes".);
1) "Squared" instructions for making 24-hours became 12-hours:
var hours24 = new Date().getHours(); // retrieve current hours (in 24 mode)
var dayMode = hours24 < 12 ? "am" : "pm"; // if it's less than 12 then "am"
var hours12 = hours24 <= 12 ? (hours24 == 0 ? 12 : hours24) : hours24 - 12;
// "0" in 24-mode now becames "12 am" in 12-mode – thanks to user #Cristian
document.write(hours12 + " " + dayMode); // printing out the result of code
2) In a single line (same result with slightly different algorythm):
var str12 = (h24 = new Date().getHours()) && (h24 - ((h24 == 0)? -12 : (h24 <= 12)? 0 : 12)) + (h24 < 12 ? " am" : " pm");
Both options return string, like "5 pm" or "10 am" etc.
You can take a look at this. One of the examples says:
var d = new Date(dateString);
Once you have Date object you can fairly easy play with it. You can either call toLocaleDateString, toLocaleTimeString or you can test if getHours is bigger than 12 and then just calculate AM/PM time.
date = date.replace(/[0-9]{1,2}(:[0-9]{2}){2}/, function (time) {
var hms = time.split(':'),
h = +hms[0],
suffix = (h < 12) ? 'am' : 'pm';
hms[0] = h % 12 || 12;
return hms.join(':') + suffix
});
edit: I forgot to deal with 12 o'clock am/pm. Fixed.
var dt = new Date();
var h = dt.getHours(), m = dt.getMinutes();
var thistime = (h > 12) ? (h-12 + ':' + m +' PM') : (h + ':' + m +' AM');
console.log(thistime);
Here is the Demo
function GetTime(date) {
var currentTime = (new Date(date))
var hours = currentTime.getHours()
//Note: before converting into 12 hour format
var suffix = '';
if (hours > 11) {
suffix += "PM";
} else {
suffix += "AM";
}
var minutes = currentTime.getMinutes()
if (minutes < 10) {
minutes = "0" + minutes
}
if (hours > 12) {
hours -= 12;
} else if (hours === 0) {
hours = 12;
}
var time = hours + ":" + minutes + " " + suffix;
return time;
}
Please try with below code
var s = "15 Feb 2015 11.30 a.m";
var times = s.match("((([0-9])|([0-2][0-9])).([0-9][0-9])[\t ]?((a.m|p.m)|(A.M|P.M)))");
var time = "";
if(times != null){
var hour = times[2];
if((times[6] == "p.m" || times[6] == "P.M")){
if(hour < 12){
hour = parseInt(hour) + parseInt(12);
}else if(hour == 12){
hour = "00";
}
}
time = [hour, times[5], "00"].join(":");
}
Thanks
This worked for me!
function main() {
var time = readLine();
var formattedTime = time.replace('AM', ' AM').replace('PM', ' PM');
var separators = [':', ' M'];
var hms = formattedTime.split(new RegExp('[' + separators.join('') + ']'));
if (parseInt(hms[0]) < 12 && hms[3] == 'P')
hms[0] = parseInt(hms[0]) + 12;
else if (parseInt(hms[0]) == 12 && hms[3] == 'A')
hms[0] = '00';
console.log(hms[0] + ':' + hms[1] + ':' + hms[2]);
}
You could try this more generic function:
function to12HourFormat(date = (new Date)) {
return {
hours: ((date.getHours() + 11) % 12 + 1),
minutes: date.getMinutes(),
meridian: (date.getHours() >= 12) ? 'PM' : 'AM',
};
}
Returns a flexible object format.
https://jsbin.com/vexejanovo/edit
I'm a relative newbie, but here's what I came up with for one of my own projects, and it seems to work. There may be simpler ways to do it.
function getTime() {
var nowTimeDate = new Date();
var nowHour = nowTimeDate.getHours();
var nowMinutes = nowTimeDate.getMinutes();
var suffix = nowHour >= 12 ? "pm" : "am";
nowHour = (suffix == "pm" & (nowHour > 12 & nowHour < 24)) ? (nowHour - 12) : nowHour;
nowHour = nowHour == 0 ? 12 : nowHour;
nowMinutes = nowMinutes < 10 ? "0" + nowMinutes : nowMinutes;
var currentTime = nowHour + ":" + nowMinutes + suffix;
document.getElementById("currentTime").innerHTML = currentTime;
}
this is your html code where you are calling function to convert 24 hour time format to 12 hour with am/pm
<pre id="tests" onClick="tConvert('18:00:00')">
test on click 18:00:00
</pre>
<span id="rzlt"></span>
now in js code write this tConvert function as it is
function tConvert (time)
{
// Check correct time format and split into components
time = time.toString ().match (/^([01]\d|2[0-3])(:)([0-5]\d)(:[0-5]\d)?$/) || [time];
if (time.length > 1)
{ // If time format correct
time = time.slice (1); // Remove full string match value
time[5] = +time[0] < 12 ? 'AM' : 'PM'; // Set AM/PM
time[0] = +time[0] % 12 || 12; // Adjust hours
}
//return time; // return adjusted time or original string
var tel = document.getElementById ('rzlt');
tel.innerHTML= time.join ('');
}
converting 18:00:00 to 6:00:00PM working for me
This function will convert in both directions:
12 to 24 hour or 24 to 12 hour
function toggle24hr(time, onoff){
if(onoff==undefined) onoff = isNaN(time.replace(':',''))//auto-detect format
var pm = time.toString().toLowerCase().indexOf('pm')>-1 //check if 'pm' exists in the time string
time = time.toString().toLowerCase().replace(/[ap]m/,'').split(':') //convert time to an array of numbers
time[0] = Number(time[0])
if(onoff){//convert to 24 hour:
if((pm && time[0]!=12)) time[0] += 12
else if(!pm && time[0]==12) time[0] = '00' //handle midnight
if(String(time[0]).length==1) time[0] = '0'+time[0] //add leading zeros if needed
}else{ //convert to 12 hour:
pm = time[0]>=12
if(!time[0]) time[0]=12 //handle midnight
else if(pm && time[0]!=12) time[0] -= 12
}
return onoff ? time.join(':') : time.join(':')+(pm ? 'pm' : 'am')
}
Here's some examples:
//convert to 24 hour:
toggle24hr('12:00am') //returns 00:00
toggle24hr('2:00pm') //returns 14:00
toggle24hr('8:00am') //returns 08:00
toggle24hr('12:00pm') //returns 12:00
//convert to 12 hour:
toggle24hr('14:00') //returns 2:00pm
toggle24hr('08:00') //returns 8:00am
toggle24hr('12:00') //returns 12:00pm
toggle24hr('00:00') //returns 12:00am
//you can also force a specific format like this:
toggle24hr('14:00',1) //returns 14:00
toggle24hr('14:00',0) //returns 2:00pm
Here you go
var myDate = new Date("February 04, 2011 19:00:00");
var hr = myDate.getHours();
var convHrs = "";
var ampmSwitch = "";
ampmSwitch = (hr > 12)? "PM":"AM";
convHrs = (hr >12)? hr-12:hr;
// Build back the Date / time using getMonth/ getFullYear and getDate and other functions on the myDate object. Enclose it inside a func and there you got the working 12 hrs converter ;)
And here's the converter func for yas ;) Happy coding!!
function convertTo12Hrs(yourDateTime){
var myDate = new Date(yourDateTime);
var dtObject = new Object();
var monthsCollection = {0:"January", 1:"February",2:"March",3:"April",4:"May",5:"June",6:"July",7:"August",8:"September",9:"October",10:"November",11:"December"};
dtObject.year = myDate.getFullYear();
dtObject.month = monthsCollection[myDate.getMonth()];
dtObject.day = (myDate.getDate()<10)?"0"+myDate.getDate():myDate.getDate();
dtObject.minutes = (myDate.getMinutes() < 10)? "0"+myDate.getMinutes():myDate.getMinutes();
dtObject.seconds = (myDate.getSeconds() < 10)? "0"+myDate.getSeconds():myDate.getSeconds();
// Check if hours are greater than 12? Its PM
dtObject.ampmSwitch = (myDate.getHours() > 12)? "PM":"AM";
// Convert the hours
dtObject.hour = (myDate.getHours() > 12)?myDate.getHours()-12:myDate.getHours();
// Add the 0 as prefix if its less than 10
dtObject.hour = (dtObject.hour < 10)? "0"+dtObject.hour:dtObject.hour;
// Format back the string as it was or return the dtObject object or however you like. I am returning the object here
return dtObject;
}
invoke it like
convertTo12Hrs("February 04, 2011 19:00:00"); it will return you the object, which in turn you can use to format back your datetime string as you fancy...
You're going to end up doing alot of string manipulation anyway,
so why not just manipulate the date string itself?
Browsers format the date string differently.
Netscape ::: Fri May 11 2012 20:15:49 GMT-0600 (Mountain Daylight Time)
IE ::: Fri May 11 20:17:33 MDT 2012
so you'll have to check for that.
var D = new Date().toString().split(' ')[(document.all)?3:4];
That will set D equal to the 24-hour HH:MM:SS string. Split that on the
colons, and the first element will be the hours.
var H = new Date().toString().split(' ')[(document.all)?3:4].split(':')[0];
You can convert 24-hour hours into 12-hour hours, but that hasn't
actually been mentioned here. Probably because it's fairly CRAZY
what you're actually doing mathematically when you convert hours
from clocks. In fact, what you're doing is adding 23, mod'ing that
by 12, and adding 1
twelveHour = ((twentyfourHour+23)%12)+1;
So, for example, you could grab the whole time from the date string, mod
the hours, and display all that with the new hours.
var T = new Date().toString().split(' ')[(document.all)?3:4].split(':');
T[0] = (((T[0])+23)%12)+1;
alert(T.join(':'));
With some smart regex, you can probably pull the hours off the HH:MM:SS
part of the date string, and mod them all in the same line. It would be
a ridiculous line because the backreference $1 couldn't be used in
calculations without putting a function in the replace.
Here's how that would look:
var T = new Date().toString().split(' ')[(document.all)?3:4].replace(/(^\d\d)/,function(){return ((parseInt(RegExp.$1)+23)%12)+1} );
Which, as I say, is ridiculous. If you're using a library that CAN perform
calculations on backreferences, the line becomes:
var T = new Date().toString().split(' ')[(document.all)?3:4].replace(/(^\d\d)/, (($1+23)%12)+1);
And that's not actually out of the question as useable code, if you document it well.
That line says:
Make a Date string, break it up on the spaces, get the browser-apropos part,
and replace the first two-digit-number with that number mod'ed.
Point of the story is, the way to convert 24-hour-clock hours to 12-hour-clock hours
is a non-obvious mathematical calculation:
You add 23, mod by 12, then add one more.
Here is a nice little function that worked for me.
function getDisplayDatetime() {
var d = new Date(); var hh = d.getHours(); var mm = d.getMinutes(); var dd = "AM"; var h = hh;
if (mm.toString().length == 1) {
mm = "0" + mm;
}
if (h >= 12) {
h = hh - 12;
dd = "PM";
}
if (h == 0) {
h = 12;
}
var Datetime = "Datetime: " + d.getFullYear() + "/" + (d.getMonth() + 1) + "/" + d.getUTCDate() + " " + h + ":" + mm;
return Datetime + " " + dd;
}
I noticed there is already an answer, but I wanted to share my own solution, using pure JavaScript:
function curTime(pm) {
var dt = new Date();
var hr = dt.getHours(), min = dt.getMinutes(), sec = dt.getSeconds();
var time = (pm ? ((hr+11)%12+1) : (hr<10?'0':'')+hr)+":"+(min<10?'0':'')+min+":"+(sec<10?'0':'')+sec+(pm ? (hr>12 ? " PM" : " AM") : "");
return time;
}
You can see it in action at https://jsfiddle.net/j2xk312m/3/ using the following code block:
(function() {
function curTime(pm) {
var dt = new Date();
var hr = dt.getHours(), min = dt.getMinutes(), sec = dt.getSeconds();
var time = (pm ? ((hr+11)%12+1) : (hr<10?'0':'')+hr)+":"+(min<10?'0':'')+min+":"+(sec<10?'0':'')+sec+(pm ? (hr>12 ? " PM" : " AM") : "");
return time;
}
alert("12-hour Format: "+curTime(true)+"\n24-hour Format: "+curTime(false));
})();
This way you have more control over the output - i.e - if you wanted the time format to be '4:30 pm' instead of '04:30 P.M.' - you can convert to whatever format you decide you want - and change it later too. Instead of being constrained to some old method that does not allow any flexibility.
and you only need to convert the first 2 digits as the minute and seconds digits are the same in 24 hour time or 12 hour time.
var my_time_conversion_arr = {'01':"01", '02':"02", '03':"03", '04':"04", '05':"05", '06':"06", '07':"07", '08':"08", '09':"09", '10':"10", '11':"11", '12': "12", '13': "1", '14': "2", '15': "3", '16': "4", '17': "5", '18': "6", '19': "7", '20': "8", '21': "9", '22': "10", '23': "11", '00':"12"};
var AM_or_PM = "";
var twenty_four_hour_time = "16:30";
var twenty_four_hour_time_arr = twenty_four_hour_time.split(":");
var twenty_four_hour_time_first_two_digits = twenty_four_hour_time_arr[0];
var first_two_twelve_hour_digits_converted = my_time_conversion_arr[twenty_four_hour_time_first_two_digits];
var time_strng_to_nmbr = parseInt(twenty_four_hour_time_first_two_digits);
if(time_strng_to_nmbr >12){
//alert("GREATER THAN 12");
AM_or_PM = "pm";
}else{
AM_or_PM = "am";
}
var twelve_hour_time_conversion = first_two_twelve_hour_digits_converted+":"+twenty_four_hour_time_arr[1]+" "+AM_or_PM;