JavaScript Dates
The Date
object is used to get information about current year, month and day.
Firstly, a Date
object is created, and then there are many javascript functions available which can operate on that object.
These functions gives provide informations like year
, month
, day
, hour
,
minute
, second
, and millisecond
, using either local time or UTC (universal, or GMT) time.
Date objects are created with the new Date()
constructor. There are 4 ways of initiating a date:
Syntax:
new Date()
new Date(milliseconds)
new Date(dateString)
new Date(year, month, day, hours, minutes, seconds, milliseconds)
JavaScript Date
In this example, first a date object is created, and then all the information about the current date and time in that object, gets displayed on the screen.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> JavaScript Date Object </title>
</head>
<body>
Current Date and Time: <span id="demo"></span>
<script>
var today=new Date();
document.getElementById('demo').innerHTML=today;
</script>
</body>
</html>
Output
JavaScript Date Object
Current Date and Time:
JavaScript Current Time
It is same as the previous one but here, the single digit in date and time will be added with zero before them. It looks good.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> JavaScript Current Date Method </title>
</head>
<body>
<h3>Current Time: </h3>
<span id="date"></span>
<script>
var today=new Date();
var h=today.getHours();
var m=today.getMinutes();
var s=today.getSeconds();
document.getElementById('date').innerHTML=h+":"+m+":"+s;
</script>
</body>
</html>
Output
JavaScript Current Date Method
Current Time:
JavaScript Current Date and Time
The JavaScript Date object can provide dates in different formats by using methods like toDateString()
, toLocaleDateString()
, etc. Look at the example below to understand it better :-
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> JavaScript Live Digital Clock </title>
</head>
<body>
Current Date and Time:<br />
<span id="digital-clock"></span>
<script>
window.onload=function(){getTime();}
function getTime(){
var today=new Date();
var h=today.getHours();
var m=today.getMinutes();
var s=today.getSeconds();
// add a zero in front of numbers<10
m=checkTime(m);
s=checkTime(s);
document.getElementById('digital-clock').innerHTML=today;
setTimeout(function(){getTime()},1000);
}
//setInterval("getTime()",1000);//another way
function checkTime(i){
if (i<10){
i="0" + i;
}
return i;
}
</script>
</body>
</html>
Output
JavaScript Live Digital Clock
Current Date and Time:
Date and Time Strings
The JavaScript Date object can provide dates in diferent formats by using methods like toLocaleDateString()
, toDateString()
etc.
Look at the example below to understand it better :
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> JavaScript Generate Date String </title>
</head>
<body>
<script>
var d = new Date();
document.write(d.toDateString() + "<br>");
document.write(d.toLocaleDateString() + "<br>");
document.write(d.toISOString() + "<br>");
document.write(d.toUTCString() + "<br>");
document.write(d.toString());
</script>
</body>
</html>
Output
JavaScript Generate Date String
Time in Hours, Minutes, Seconds, and Milliseconds
The Date object also provide some methods to extract time components individually like getHours()
, getMinutes()
, getSeconds()
, etc.
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="UTF-8">
<title> JavaScript Date </title>
</head>
<body>
<script>
var date = new Date();
// Extracting time part
document.write("Hours : " + date.getHours() + "<br>");
document.write("Minutes : " + date.getMinutes() + "<br>");
document.write("Seconds : " + date.getSeconds() + "<br>");
document.write("Miliseconds : " + date.getMilliseconds() + "<br>");
document.write("Time : " + date.getTime() + "<br>");
document.write("Time Zone : " + date.getTimezoneOffset());
</script>
</body>
</html>
Output
Note : The getTime() method returns the number of milliseconds between midnight of
January 1, 1970 and the specified date.