<body>
<input type="button" name="" value="Create" onclick="add()" />
<hr width="245px" size="1" align="left" />
<input type="text" name="" value="" id="txt" />
<ol id="oList">
<li>Black metal</li>
<li>Alternative metal</li>
<li>Thrash metal</li>
<li>Doom metal</li>
<li>Classical metal</li>
<li>Gothic metal</li>
</ol>
</body>
<script type="text/javascript">
function add(){
var oList = document.getElementById("oList");
var listItems = document.createElement("li");
//listItems.innerHTML = txt.value;//这样写也能将文本框输入的值赋予到添加的LI元素中
listItems.innerHTML = document.getElementById("txt").value;
oList.appendChild(listItems);
}
</script>