June 11, 2013

JavaScript Check If Element Has Class

Posted In: "development"

Here is a little snippet If you’re trying to check wether element contains a class, without using jQuery.

function hasClass(element, className) {
    return element.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(element.className);
}

This accounts for the fact that element might contain multiple class names separated by space.

You can also assign this function to element prototype.

Element.prototype.hasClass = function(className) {
    return this.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(this.className);
};

And trigger it like this (very similar to jQuery’s .hasClass() function):

document.getElementById('MyDiv').hasClass('active');