js replaceChild

//父亲元素.replaceChild(新，旧)

 1     <ul id="city">
         <li id="bj">北京</li>
         <li id="sh">上海</li>
         <li id="gz">广州</li>
     </ul>

     <ul id="color">
         <li id="red">红色</li>
         <li id="green">绿色</li>
         <li id="blue">蓝色</li>
     </ul>
     <script type="text/javascript">
         var gzLiElement=document.getElementById("gz");
         gzLiElement.onclick=function(){
             var colorElement=document.getElementById("color");
             //父亲元素.replaceChild(新，旧)
             document.getElementById("city").replaceChild(colorElement,this);
             alert("xx");
         }