Check if an element contains a class in JavaScript?

Question

Using plain JavaScript (not jQuery), Is there any way to check if an element contains a class?

Currently, I\'m doing this:

Answer 1

I created these functions for my website, I use only vanilla javascript, maybe it will help someone. First I created a function to get any HTML element:

//return an HTML element by ID, class or tag name
    var getElement = function(selector) {
        var elements = [];
        if(selector[0] == '#') {
            elements.push(document.getElementById(selector.substring(1, selector.length)));
        } else if(selector[0] == '.') {
            elements = document.getElementsByClassName(selector.substring(1, selector.length));
        } else {
            elements = document.getElementsByTagName(selector);
        }
        return elements;
    }

Then the function that recieve the class to remove and the selector of the element:

var hasClass = function(selector, _class) {
        var elements = getElement(selector);
        var contains = false;
        for (let index = 0; index < elements.length; index++) {
            const curElement = elements[index];
            if(curElement.classList.contains(_class)) {
                contains = true;
                break;
            }
        }
        return contains;
    }

Now you can use it like this:

hasClass('body', 'gray')
hasClass('#like', 'green')
hasClass('.button', 'active')

Hope it will help.