These JavaScript snippets implement a native hasClass() function, which checks if an element has a certain class.
// Method #1: Use JavaScript element.className
function elementHasClass(element, className) {
return (element.className === className);
}
// Method #2: Use JavaScript element attribute getter
function elementHasClass(element, className) {
return (indexOf(element.getAttribute(className)));
}
// Method #3: Use JavaScript element.className (RegEx)
function elementHasClass(element, className) {
return element.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(element.className);
}
// Usage
if (elementHasClass(document.querySelector('.element'), 'active')) {
// Do this or do that
}A prototype approach to the above solution is:
// Method #4: Prototype
Element.prototype.elementHasClass = function(className) {
return this.className && new RegExp("(^|\\s)" + className + "(\\s|$)").test(this.className);
};
// Usage
if (document.querySelector('.element').elementHasClass('active')) {
// Do this or do that
}Personally, I would steer away from the RegEx ones, namely methods 3 and 4.
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