<head> <meta http-equiv="Content-Type" content="text/html;charset=UTF-8" /> <title>当鼠标经过换一张相片</title> <meta name="keywords" content="关键字列表" /> <meta name="description" content="网页描述" /> <link rel="stylesheet" type="text/css" href="" /> <style type="text/css"></style> <script type="text/javascript"></script> </head> <body> </body> </html> <img src="jd1.png" id="img1"> <script type="text/javascript"> var imgObj=document.getElementById("img1");//对象.属性=（""），对象.方法（""） imgObj.onmouseover=function(){ imgObj.src="jd2.png" } imgObj.onmouseout=function(){ imgObj.src="jd1.png" } </script>
原文：http://www.cnblogs.com/91xiaozhu/p/6087831.html