js实现addClass,removeClass,hasClass

源地址:http://snipplr.com/view/3561/addclass-removeclass-hasclass/


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};