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Javascript-is commonly used to validate user input

Source: Internet
Author: User
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JavaScript is the most popular programming language in the world.

The language can be used in HTML and the Web, and is more widely used in servers, PCs, laptops, tablets and smartphones.



JavaScript is a scripting language

JavaScript is a lightweight programming language.

JavaScript is a programmatic code that can be inserted into an HTML page.

When JavaScript is inserted into an HTML page, it can be performed by all modern browsers.

JavaScript is easy to learn.


Commonly used to validate the user's input:

<! DOCTYPE html>

<meta http-equiv= "Content-type" content= "text/html; Charset=utf-8 "/>
<center>
<body>
<p> Please enter a number. If the input value is not a number, the browser pops up the prompt box. </p>
<input id= "Demo" type= "text" >

<script>
function MyFunction ()
{
var X=document.getelementbyid ("Demo"). Value;
if (x== "" | | IsNaN (x))
{
Alert ("Not Numeric");
}
</script>

<button type= "button" onclick= "MyFunction ()" > Click Start </button>
</body>
</center>

Javascript-is commonly used to validate user input

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Related Keywords:
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