1、var oTbody = oTab.tBodies[0]; 2、oTd.innerHTML = oTbody.rows.length + 1;
<!DOCTYPE >
<html>
<head>
<title></title>
<meta charset="utf-8">
<script>
window.onload = function() {
var oTab = document.getElementById('tab1');
var oTbody = oTab.tBodies[0];
var oName = document.getElementById('name'); // 姓名
var oAge = document.getElementById('age'); // 年龄
var oAddBtn = document.getElementById('add'); // 新增(按钮)
oAddBtn.onclick = function() {
var oTr = document.createElement('tr');
var oTd = document.createElement('td');
oTd.innerHTML = oTbody.rows.length + 1; // 自增ID
oTr.appendChild(oTd);
var oTd = document.createElement('td');
oTd.innerHTML = oName.value;
oTr.appendChild(oTd);
var oTd = document.createElement('td');
oTd.innerHTML = oAge.value;
oTr.appendChild(oTd);
oTbody.appendChild(oTr);
}
}
</script>
</head>
<body>
姓名:<input type="text" name="name" id="name" value="Tom" /> 年龄:
<input type="text" name="age" id="age" value="20" />
<input type="button" name="add" id="add" value="新增" />
<table id="tab1" width="300" border="1">
<thead>
<td>ID</td>
<td>姓名</td>
<td>年龄</td>
</thead>
<tbody>
<tr>
<td>1</td>
<td>Blue</td>
<td>27</td>
</tr>
<tr>
<td>2</td>
<td>张三</td>
<td>23</td>
</tr>
</tbody>
</table>
</body>
</html>
QQ20190403-085101.gif