怎么在表格里插入一行
<table name="table1" align="center" border=1>
<tr>
<td width="80%" align="center" background="fffff">
ddddf
</td>
<td>
dddddd
<td>
</tr>
</table>
<script language="javascript">
var thetable=document.all("table1");
newrow=thetable.insertRow(0);
newcell=newrow.insertCell();
newcell.innerText="dfd";
</script>
结果出错提示说thetable不是对象,为什么?