JS_attr函數

/*
 * 考慮到getAttribute(),在IE6,7下對class有兼容性問題所以使用getAttributeNode();
 * removeNamedItem(),在IE6,7下動態添加屬性后,表現異常.所以使用removeAttribute();
 */
<div title="hello" id="main" dir="rtl" mytitle="whoat">my!</div>
<script type="text/javascript">
var attr = function(ele,name,value){
    if(!ele) return;
    if(!!value){
        var _att = document.createAttribute(name);
        _att.nodeValue = value;
        ele.setAttributeNode(_att);
        return;
        }
    if(!!ele.getAttributeNode(name)){
        var _val = ele.getAttributeNode(name).nodeValue;
        return _val;
        }else{
        return null;
        }
    }
var removeAttr = function(ele,name){
    if(!ele) return;
    switch(name){
        case "class":
        case "className":
         ele.removeAttribute("class");
         ele.removeAttribute("className");
         break;
        default: 
         ele.removeAttribute(name);
        }
    }
var main = document.getElementById("main");
attr(main,"class","main");
removeAttr(main,"dir");
</script>