页面图片地址问题（在线）

<head>
<title> New Document </title>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312" />
<meta name="title" content="" />
<meta name="author" content="活靶子,Huobazi,www.AspxBoy.com" />
<meta name="subject" content="" />
<meta name="language" content="gb2312" />
<meta name="keywords" content="" />
<meta name="Copyright" content="www.AspxBoy.com" />
<meta name="robots" content="all" /> </head>
<body>
<br />
<br /><br/>
<img id="myimg" src="http://community.csdn.net/images/CSDN_logo.GIF" />
<button onclick="document.getElementById('myimg').src='http://community.csdn.net/images/ad/banner7.GIF';">ChangeImage</button></body>
</html>