复制代码 代码如下:

function hasClass(ele,cls) {

return ele.className.match(new RegExp('(s|^)'+cls+'(s|$)'));

}

function addClass(ele,cls) {

if (!this.hasClass(ele,cls)) ele.className += " "+cls;

}

function removeClass(ele,cls) {

if (hasClass(ele,cls)) {

var reg = new RegExp('(s|^)'+cls+'(s|$)');

ele.className=ele.className.replace(reg,' ');

}

}

//call the functions

addClass(document.getElementById("test"), "test");

removeClass(document.getElementById("test"), "test")

if(hasClass(document.getElementById("test"), "test")){//do something};