HTML with JavaScript

JavaScript makes HTML pages more dynamic and interactive. With JavaScript Someone can change the CSS property, content, and many more in realtime.

Example

My First JavaScript

The HTML <script> Tag

The HTML <script> tag is used to define a client-side script (JavaScript).

Client-side script : The Client-size script is the code which runs on the user's device to perform any function.

The <script> element either contains script statements, or it points to an external script file through the src attribute.

<script src="p.js"/>

Common uses for JavaScript are image manipulation, form validation, and dynamic changes of content.

• It changes the source of an image.
• It takes user input and send to server.
• It changes the content of web page in realtime and many more...

To select an HTML element, JavaScript most often uses the document.getElementById() method.

This JavaScript example alert "Hello JavaScript!" into the user's browser.

Example

<script>

window.alert("Hello JavaScript!");

</script>

A Taste of JavaScript

Here are some examples of what JavaScript can do:

Div with id "demo" :

<div>

Example

JavaScript can change content:

document.getElementById("demo").innerHTML = "Hello JavaScript!";

Example

JavaScript can change styles:

document.getElementById("demo").style.fontSize = "25px";

document.getElementById("demo").style.color = "red";

document.getElementById("demo").style.backgroundColor = "yellow";

Example

JavaScript can change attributes:

document.getElementById("image").src = "picture.gif";

The HTML <noscript> Tag

The HTML <noscript> tag defines an alternate content to be displayed to users that have disabled scripts in their browser or have a browser that doesn't support scripts:

Example

<script>

alert("Hello JavaScript!");

</script>

<noscript>Sorry, your browser does not support JavaScript!</noscript>