js插入html代码

点击button，例如:

<button>按钮</button>

添加 <button class="condition-btn">按钮</button>

到

<div id="chart-body" class="chart-body"></div> 中

该如何写？

---

$("button").click(function(){
     $("#chart-body").append("<button class='condition-btn'></button>");
     var btnText = $("button").text();
     $(".condition-btn").text(btnText);
})

---

<script type="text/javascript">
        window.onload=function(){
            var aBtn=document.getElementsByTagName('button');
            var oDiv=document.getElementById('chart-body');
            aBtn[0].onclick=function(){
                oDiv.innerHTML+='<button class="condition-btn">按钮</button>';
            }
        }        
    </script>