<!DOCTYPE HTML> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=utf-8"> <title>无标题文档</title> <script> window.onload=function(){ var oDiv=document.getElementById('di'); var oDiv2=document.getElementById('di1'); addClass(oDiv,'boee'); remove(oDiv2,'box2'); function addClass(obj,className) { if(obj.className==null) {obj.className=className;} else{ var arrClassName=obj.className.split(' '); var _index=arrIndexOf(arrClassName,className ); if(_index==-1) { obj.className+=' '+className; }else{ } } } function arrIndexOf(arr,v){ for(var i=0;i<arr.length;i++) { if(arr[i]==v) {return i;} } return -1; } function remove(obj,className){ if(className!=''){ var arrClassName=obj.className.split(' '); var _index=arrIndexOf(arrClassName,className ); if(_index!=-1) { arrClassName.splice(_index,1); obj.className=arrClassName.join(' '); } } } }; </script> </head> <body> <div class="box box2" id='di'>div1</div> <div class="box box2" id='di1'>div2</div> </body> </html>