Working with time

Along with the date components, the Date object stores time information as well. The following methods provide access to a Date object's time information:

  • getHours Returns the hour portion of the time.
  • getMinutes Returns the minutes portion of the time.
  • getSeconds Returns the seconds portion of the time.
  • getMilliseconds Returns the milliseconds portion of the time.
  • getTime Returns the number of milliseconds since midnight January 1, 1970.
  • getTimezoneOffset Returns the difference in minutes between local time and Greenwich Mean Time (GMT).
  • getUTCHours Returns the hour portion of the time according to UTC.
  • getUTCMinutes Returns the minutes portion of the time according to UTC.
  • getUTCSeconds Returns the seconds portion of the time according to UTC.
  • getUTCMilliseconds Returns the milliseconds portion of the time according to UTC.
As previously demonstrated, you can initialize a Date object by passing in the hours, minutes, and seconds, but the milliseconds property is set via the setMilliseconds method. This JavaScript displays the current time:
<script language="javascript">
var d = new Date();
document.write(d.getHours() + ":" + d.getMinutes() + ":"
  + d.getSeconds() + ":" + d.getMilliseconds());
document.write(d.getTime());

</script>
It displays the following output: 
12:36:33:41

1146760593041
The second value is a bit odd since it displays the number of milliseconds since January 1, 1970 to the value stored in the referenced Date object. It comes in handy when finding the difference between two values. As with date values, a setTime method is available as well: 
Var dt1 = new Date();
var dt2 = new Date(1970, 4, 15);

dt1.setTime(dt2.getTime());
Setting properties
Like the setTime, setDate, and setMilliseconds methods, there are methods to populate all portions of a Date object. This includes the following:
  • setFullYear
  • setHours
  • setMinutes
  • setMilliseconds
  • setMonth
  • setSeconds
  • setUTCFullYear
  • setUTCMonth
  • setUTCHours
  • setUTCSeconds
  • setUTCMilliseconds
These methods allow you to easily reset a date property by passing in its new value. It's good to be able to work with and display dates, but there will be times when you need to perform calculations with dates and so forth.
12 34 Next >

Do you need help with Web Technologies? Gain advice from Builder AU forums

Related links

Comments

1

Sudip Dey - 05/03/08

codes are simple to understand....also give code which autorefresh the time....
I need your comments also.... 

<html>

<head>

	<title>Digital Clock</title>

<style>

<!--

.styling{

background-color:black;

color:lime;

font: bold 15px MS Sans Serif;

padding: 3px;

}

-->

</style>

</head>



<body>

<span id="digitalclock" class="styling"></span>



<script>

<!--



/*****************************************

* LCD Clock script- by Javascriptkit.com

* Featured on/available at http://www.dynamicdrive.com/

* This notice must stay intact for use

*****************************************/



var alternate=0

var standardbrowser=!document.all&&!document.getElementById



if (standardbrowser)

document.write('<form name="tick"><input type="text" name="tock" size="6"></form>')



function show(){

if (!standardbrowser)

var clockobj=document.getElementById? document.getElementById("digitalclock") : document.all.digitalclock

var Digital=new Date()

var hours=Digital.getHours()

var minutes=Digital.getMinutes()

var dn="AM"



if (hours==12) dn="PM" 

if (hours>12){

dn="PM"

hours=hours-12

}

if (hours==0) hours=12

if (hours.toString().length==1)

hours="0"+hours

if (minutes<=9)

minutes="0"+minutes



if (standardbrowser){

if (alternate==0)

document.tick.tock.value=hours+" : "+minutes+" "+dn

else

document.tick.tock.value=hours+"   "+minutes+" "+dn

}

else{

if (alternate==0)

clockobj.innerHTML=hours+"<font color='lime'>&nbsp;:&nbsp;</font>"+minutes+" "+"<sup style='font-size:1px'>"+dn+"</sup>"

else

clockobj.innerHTML=hours+"<font color='black'>&nbsp;:&nbsp;</font>"+minutes+" "+"<sup style='font-size:1px'>"+dn+"</sup>"

}

alternate=(alternate==0)? 1 : 0

setTimeout("show()",1000)

}

window.onload=show



//-->

</script>

</body>

</html>

» Report offensive content

2

Linda - 01/10/08

As part of my job, I add an expiration date to secured spec. The date is to be 1 week from the day someone prints or opens a specific spec. My problem is that it only works on 98 computers and not XP. I inherited the code and am not too familar with JavaScrip. Can you tell me why this does not work on XP computers?
Thanks for you time. 

/* Example of date arithmetic. */

/* Create a date object containing the current date. */

var d1 = new Date();

/* num contains the numeric representation of the current date. */

var num = d1.valueOf();

/* Add seven days to today’s date. */

/* 1000 ms / sec; 60 sec / min; 60 min / hour; 24 hours / day; 7 days */

num += 1000 * 60 * 60 * 24 * 7;

/* Create our new date that is 7 days ahead of the current date. */

var d2 = (new Date(num));

/* Add text. */

var d3 = "Document Expires:";

/* Print out the current date and our new date using util.printd */

var f = this.getField("Today1");

f.value = d3 +(util.printd("mm/dd/yyyy", d2));

» Report offensive content

Leave a comment

You must read and type the 6 chars within 0..9 and A..F

* indicates mandatory fields.

Latest comments

2

Linda - 10/01/08

As part of my job, I add an expiration date to secured spec. The date is to be 1 week ... more

1

Sudip Dey - 03/05/08

codes are simple to understand....also give code which autorefresh the time.... I need your comments also.... <html> <head> <title>Digital Clock</title> <style> <!-- .styling{ background-color:black; color:lime; font: bold 15px MS Sans ... more

Log in


Sign up | Forgot your password?

Blogs

RSS feed

What's on?