关于 removeClass ，这两种方式，有哪个好些 ？该怎么处理

function removeClass(node,removeName){
    var origClass = node.className;
    node.className = origClass.replace(removeName,"");
}    

Object.prototype.removeClass=function(removeName){                    
    var origClass = this.className;
    his.className = origClass.replace(removeName,"");
}