------解决思路----------------------
$(document).ready(function() {
$("#btn").click(function() {
var input = '<input id="text1" type="text">';
$("#div1").append(input);
});
});<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<title>demo.htm</title>
<script type="text/javascript" src="js/jquery/jquery-1.7.2.js"></script>
<script type="text/javascript" src="js/demo.js"></script>
</head>
<body>
<input type="button" id="btn" value="请点击">
<div id="div1"></div>
</body>
</html>