insertAdjacentHTML的用法

<script language="javascript">
function insertHTML(){
window.event.srcElement.insertAdjacentHTML('BeforeBegin','<input id="oInput">');
document.all['delete'].disabled = false;
}
function deleteHTML(){
document.all['oInput'].removeNode(true);
window.event.srcElement.disabled = true;
}
</script>
<input type="button" id="add" value="添加" onclick="insertHTML();">
<input type="button" id="delete" value="删除" onclick="deleteHTML();" disabled>