Manage Class

ManageClass

var manageClass = {},
    hasClass, addClass, removeClass, toggleClass;

if ('classList' in document.documentElement) {
    hasClass = function(elem, className) {
        return elem.classList.contains(className);
    };
    addClass = function(elem, className) {
        elem.classList.add(className);
    };
    removeClass = function(elem, className) {
        elem.classList.remove(className);
    };
    toggleClass = function(elem, className) {
        elem.classList.toggle(className);
    };
} else {
    hasClass = function(elem, className) {
        return new RegExp('(^|\\s)' + className + '(\\s|$)').test(elem.className);
    };
    addClass = function(elem, className) {
        if (!hasClass(elem, className)) {
            elem.className += (elem.className ? ' ' : '') + className;
        }
    };
    removeClass = function(elem, className) {
        if (hasClass(elem, className)) {
            elem.className = elem.className.replace(new RegExp('(^|\\s)*' + className + '(\\s|$)*', 'g'), '');
        }
    };
    toggleClass = function(elem, className) {
        (hasClass(elem, className) ? removeClass : addClass)(elem, className);
    };
}

manageClass.hasClass = hasClass;
manageClass.addClass = addClass;
manageClass.removeClass = removeClass;
manageClass.toggleClass = toggleClass;

window.manageClass = manageClass;