​x
 
<html>
<head>
<style>
input
{
background-image:url('/i/eg_bg_03.gif');
width:156px;
height:111px;
}
</style>
<script type="text/javascript">
function over()
{
if (event.srcElement.tagName=="INPUT")
    {
    event.srcElement.style.backgroundImage="url('/i/eg_bg_04.gif')"
    }
}
​
function out()
{
if (event.srcElement.tagName=="INPUT")
    {
    event.srcElement.style.backgroundImage="url('/i/eg_bg_07.gif')"
    }
}
</script>
</head>
​
<body>
<p>请把鼠标移动到图像上：</p>
<form onmouseout="out()" onmouseover="over()">
<input class="a" type="button" value="按钮 1"><br />
<input class="b" type="button" value="按钮 2"><br />
<input class="c" type="button" value="按钮 3"><br />
</form>
</body>
​
</html>
​