Introduction to JavaScript Countdown
In Countdown is one of the feature for counting the times by using date and time() methods whenever we want the count timer or countdown of the any features available as we mentioned in the html web pages or any other UI pages link with the script language the date() is the method also we have to create the instance of the data object same thing in timestamp we used getTime() method for getting the time with the help of date() instance. The countDownDate and time also vary sometimes time will calculate milliseconds and date format also applicable based on the user requirement.
Syntax and Parameters
Whenever we needs the countdown feature we will use the date() instance for getting the time intervals in either type.The basic syntax as follows.
<html>
<head>
<script>
var v=new Date("").getTime();
var v1=setInterval(function name(){
-----we can write the codes like date,time calculation for both hours,minutes and seconds even though we also calculate the milliseconds they have the some default formulas for getting the above requirement.---
}
</script></head>
<body></body></html>We can see the above codes we have to create the date instance and manually set the time interval for hours,minutes,seconds format for each requirement we have used the method called Math.floor() method for calculating the above scenarios using the formulas.
How is Countdown Done in JavaScript?
The javascript countdown timer will create the timer settings for user prospective we have to declare the variables first and that it holds the date and time objects also we want our countdown timers to run down it.Mainly we will focus to create the Date Object and then we call the method like getTime() to use on this instance.The getTime() method its makes the countDownDate variables it holds the milliseconds since the date is started like Jan 1,0000,00:00.000 GMT.The JavaScript function will used for utilizing and create the var datatypes and it makes to run for every time seconds using the setInterval() method for set the time intervals.We can calculate the time differences in milliseconds in between the current date and end date once we can calculate the date differences next step we can calculate the time as milliseconds format into days, hours, minutes, and seconds.
Once we used countdown options in script it takes appropriate actions for the countdown time is going to be end it measures and clears the values for days, hours, minutes, and seconds and it displays the heading when the timer is up we can also stop the scripts for executing the functions using clearInterval method.The timer saves and it can server many purposes because they can communicate to the user how much it would long with they have been doing something or how much time they save it for until the some event happens like the launch of the new websites.We all know about to calculate the remaining time with the help of current actual time and the time that goes to the countdown for it will expired the difference is noted and they used.Most probably we may noticed the times that we have countdown for the new year’s day so that we will use the upcoming new year as our end time calculation for the countdown time.We may use + operator in the before new Date() object creation it’s nothing but the shorthand property to tell the javascript for casting the object as an integer which gives the object’s Unix time stamp and it represented the time as milliseconds format since the epoch format type is used.
Examples of JavaScript Countdown
Following are the examples as given below:
Example #1
Code:
<!DOCTYPE HTML>
<html>
<head>
<meta name="viewport"content="width=device-width, initial-scale=1">
<style>
p {
text-align: center;
font-size: 60px;
margin-top: 0px;
}
</style>
</head>
<body>
<p id="ex"></p>
<script>
var c = new Date("July 18, 2020 23:30:20").getTime();
var t = setInterval(function() {
var n = new Date().getTime();
var d = c - n;
var da = Math.floor(d / (1000 * 60 * 60 * 24));
var h = Math.floor((d % (1000 * 60 * 60 * 24)) / (1000 * 60 * 60));
var m = Math.floor((d % (1000 * 60 * 60)) / (1000 * 60));
var s = Math.floor((d % (1000 * 60)) / 1000);
document.getElementById("ex").innerHTML = da + "d " + h + "h "
+ m + "m " + s + "s ";
if (d < 0) {
clearInterval(t);
document.getElementById("ex").innerHTML = "EXPIRED";
}
}, 1000);
</script>
</body>
</html>Output:
Example #2
Code:
<!DOCTYPE html>
<html>
<body>
<div id="ex"></div>
<script>
function demo() {
const d = +newDate("2020-07-20") - +new Date();
let r = "Time's up its a past day!";
if (d > 0) {
const p = {
days: Math.floor(d / (1000 * 60 * 60 * 24)),
hours: Math.floor((d / (1000 * 60 * 60)) % 24),
minutes: Math.floor((d / 1000 / 60) % 60),
seconds: Math.floor((d / 1000) % 60)
};
r = Object.keys(p)
.map(p1 => {
if(!p[p1]) return;
return `${p[p1]} ${p1}`;
})
.join(" ");
}
document.getElementById("ex").innerHTML = r;
}
demo();
setInterval(demo, 1000);
</script>
</body>
</html>Output:
Example #3
Code:
<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<title>Welcome To My Domain</title>
<style>
#sample{
background: #000;
padding: 20px;
margin: 20px 0;
color: lime;
display: block;
font: 48px monospace;
}
</style>
</head>
<body>
<script>
var t;
function alertDelay() {
t = setTimeout(Alertdisplay, 2000);
}
function Alertdisplay() {
alert('Welcome User thank you for choosing the Alert features');
}
function alertClear() {
clearTimeout(t);
}
var i;
function time() {
var date = new Date();
document.getElementById("sample").innerHTML = date.toLocaleTimeString();
}
function timeStop() {
clearInterval(i);
}
var i = setInterval(time, 1000);
</script>
<button onclick="alertDelay();">Show me the Alert After 2 second of your time</button>
<button onclick="alertClear();">Cancel the Alert user settings</button>
<p>Current Time of your Machine is: <span id="sample"></span></p>
<button onclick="timeStop();">Time is stopped</button>
</body>
</html>Output:
Conclusion
These countdown timers have used on the web with different scenarios and also they can find on the websites with more products and services with the countdown timer features and it displaying the times as correct scenarios like until their web based products or customer services has been launched.
Recommended Articles
This is a guide to JavaScript Countdown. Here we also discuss the introduction and how does countdown done in javascript? along with different examples and its code implementation. You may also have a look at the following articles to learn more –
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