JavaScript动态操作HTML元素：添加与删除详解

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>测试文档</title> 
<script type="text/javascript"> 
function add(){ 
var element = document.createElement("p"); 
var node = document.createTextNode("添加新段落"); 
element.appendChild(node); 
x = document.getElementById("demo"); 
x.appendChild(element); 
} 
</script> 
</head> 
<body> 
<div id="demo"> 
<p>这是第一段</p> 
</div> 
<input type="button" value="按钮" onclick="add()" /> 
</body> 
</html>

<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd"> 
<html xmlns="http://www.w3.org/1999/xhtml"> 
<head> 
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" /> 
<title>测试文档</title> 
<script type="text/javascript"> 
function deleteE(){ 
var father = document.getElementById("demo"); 
var child = document.getElementById("p1"); 
father.removeChild(child); 
} 
</script> 
</head> 
<body> 
<div id="demo"> 
<p id="p1">这是第一段</p> 
<p id="p2">这是第二段</p> 
</div> 
<input type="button" value="删除" onclick="deleteE()" /> 
</body> 
</html>