function createRow()
{
var showTable=document.getElementById("myTable");
var newTr=showTable.insertRow(-1);
var newTdA= newTr.insertCell(-1);
var newTdB= newTr.insertCell(-1);
newTdA.innerHTML="terry";
newTdB.innerHTML="1234";
}
{
var showTable=document.getElementById("myTable");
var newTr=showTable.insertRow(-1);
var newTdA= newTr.insertCell(-1);
var newTdB= newTr.insertCell(-1);
newTdA.innerHTML="terry";
newTdB.innerHTML="1234";
}
{
var showTable=document.getElementById("myTable");
var newTr=showTable.insertRow(showTable.rows.length);
var newTdA= newTr.insertCell(newTr.cells.length);
var newTdB= newTr.insertCell(newTr.cells.length);
newTdA.innerHTML="terry";
newTdB.innerHTML="1234";
}
<tr><th>用户名</th><th>密码</th></tr>
</table>
<input type="button" onClick="createRow()" value="插入行">
<script language="javascript">
function createRow()
{
var showTable=document.getElementById("myTable");
var newTr=showTable.insertRow(showTable.rows.length);
var newTdA= newTr.insertCell(newTr.cells.length);
var newTdB= newTr.insertCell(newTr.cells.length);
newTdA.innerHTML="terry";
newTdB.innerHTML="1234";
}
</script>