Using JQuery Add A New Class To An Element That Already Has A Class

jQuery: Using jQuery add a new class to an element that already has a class Last update on July 22 2025 13:05:11 (UTC/GMT +8 hours)

jQuery Fundamental - I : Exercise-7

Using jQuery add a new class to an element that already has a class.

Add the "w3r_bg_blue" class to a paragraph that already has a "w3r_bg_orange" class

<p class="w3r_bg_orange">The best way we learn anything is by practice and exercise questions.</p> p { background: white; } .w3r_bg_orange{ background: orange; } .w3r_bg_red { color: red; }

Sample solution :

HTML Code :

<!DOCTYPE html> <html> <head> <script src="https://code.jquery.com/jquery-git.js"></script> <meta charset="utf-8"> <meta name="viewport" content="width=device-width"> <title>JS Bin</title> </head> <body> <p class="w3r_bg_orange">The best way we learn anything is by practice and exercise questions.</p> <button id="button1">Click to see the effect</button> </body> </html>

CSS Code:

button { display: block; margin: 20px 0 0 0; } p { background: white; } .w3r_bg_orange{ background: orange; } .w3r_bg_red { color: red; }

JavaScript Code :

$('#button1').click(function(){ $( "p" ).addClass(function( index, currentClass ) { var addedClass; if ( currentClass === "w3r_bg_orange" ) { addedClass = "w3r_bg_red"; } return addedClass; }); });

Used Methods :

  • .addClass() : Adds the specified class(es) to each element in the set of matched elements

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See the Pen jquery-fundamental-exercise-7 by w3resource (@w3resource) on CodePen.

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