老师授课-2-点击之后变化

 1 <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Transitional//EN" "http://www.w3.org/TR/xhtml1/DTD/xhtml1-transitional.dtd">
 2 <html xmlns="http://www.w3.org/1999/xhtml">
 3 <head>
 4 <meta http-equiv="Content-Type" content="text/html; charset=utf-8" />
 5 <title>无标题文档</title>
 6 
 7 </head>
 8 
 9 <body>
10 <br />
11 <div id="me"><b>试试吧</b></div><br />
12 
13 <input type="button" value="请点击" onclick="change()" />
14 </body>
15 </html>
16 <script>
17 function change()
18 {
19     var a =document.getElementById("me");
20     a.innerHTML="<font color='red'>Hello world!</font>";    
21 }
22 </script>
运行
点击之前
点击之后