运行效果如图（两种实现方案，被注释的是第一种实现方案）
代码：
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<title></title>
</head>
<style type="text/css">
div{
text-align:center;
box-sizing: border-box;
width:100%;
}
#div1{
margin-left: 300px;
width: 800px;
margin-top: 50px;
}
#div2{
margin-left: 300px;
width: 800px;
padding-top:50px;
}
#table_id{
width: 580px;
}
</style>
<body>
<div id="div0">
<div id="div1">
<input type="text" id="userid" placeholder="请输入编号" />
<input type="text" id="username" placeholder="请输入姓名" />
<input type="text" id="gender" placeholder="请输入性别" />
<input type="button" value="添加" id="add"/>
</div>
<div id="div2">
<table border="1px" align="center" id="table_id">
<caption style="font: '微软雅黑';font-size:20px;">学生信息表</caption>
<tr>
<th>编号</th>
<th>姓名</th>
<th>性别</th>
<th>操作</th>
</tr>
<tr>
<td>1</td>
<td>令狐冲</td>
<td>张无忌</td>
<td><input type="button" value="删除" style="color: blue;" onclick="delTr(this)"/></td>
</tr>
<tr>
<td>1</td>
<td>令狐冲</td>
<td>张无忌</td>
<td><input type="button" value="删除" style="color: blue;" onclick="delTr(this)" /></td>
</tr>
<tr>
<td>1</td>
<td>令狐冲</td>
<td>张无忌</td>
<td><input type="button" value="删除"style="color: blue;" onclick="delTr(this)"/></td>
</tr>
</table>
</div>
</div>
</body>
<script type="text/javascript">
// 当点击添加按钮时触发下面的方法
document.getElementById("add").onclick=function(){
// 获取每个文本框中的内容
var id = document.getElementById("userid").value;
var name = document.getElementById("username").value;
var gender = document.getElementById("gender").value;
/* // 添加id
var td_id = document.createElement("td");
var text_id = document.createTextNode(id);
td_id.appendChild(text_id);
// 添加username
var td_username = document.createElement("td");
var text_username = document.createTextNode(name);
td_username.appendChild(text_username);
// 添加gender
var td_gender = document.createElement("td");
var text_gender = document.createTextNode(gender);
td_gender.appendChild(text_gender);
// 添加按钮
var td_button = document.createElement("td");
var ele_input = document.createElement("input");
ele_input.setAttribute("type","button");
ele_input.setAttribute("value","删除");
ele_input.setAttribute("onclick","delTr(this)");
ele_input.style.color="blue";
td_button.appendChild(ele_input);
var ele_tr = document.createElement("tr");
ele_tr.appendChild(td_id);
ele_tr.appendChild(td_username);
ele_tr.appendChild(td_gender);
ele_tr.appendChild(td_button);
var ele_table = document.getElementsByTagName("table")[0];
ele_table.appendChild(ele_tr);*/
// 使用innerHtml的方法动态添加表格
var tab = document.getElementsByTagName("table")[0];
tab.innerHTML+="<tr>\n"+
"<td>"+id+"</td>\n"+
"<td>"+name+"</td>"+
"<td>"+gender+"</td>"+
"<td><input type='button' value='删除' onclick='delTr(this)' style='color:blue'/></td>"+
"</tr>"
}
function delTr(obj){
var table = obj.parentNode.parentNode.parentNode;
var tr = obj.parentNode.parentNode;
table.removeChild(tr);
}
</script>
</html>
