Here you can find the source of hasClass(classname)
// Element HasClass Element.prototype.hasClass = function (classname) { if (this == null) throw new TypeError(); return this.className.split(' ').indexOf(classname) === -1 ? false : true; }
Element.prototype.hasClass = function(cls) { return this.className.match(new RegExp('(\\s|^)'+cls+'(\\s|$)')); };
Element.prototype.hasClass=function(selector){ if((" " + this.className + " ").replace(/[\n\t]/g, " ").indexOf(" " + selector + " ") > -1 ){ return true; return false; };
Element.prototype.hasStyleClass = function(className) { if (!className) return false; if (this.className === className) return true; var regex = new RegExp("(^|\\s)" + className.escapeForRegExp() + "($|\\s)"); return regex.test(this.className); };
HTMLElement.prototype.classContains = function() { var args = arguments; if (args.length < 1) { return false; for (var i = 0; i < args.length; i++) { var classList = this.classList; if (!classList.contains(args[i])) { return false; ...