​x
 
<html>
<body>
​
<img src="/i/eg_planets.jpg"
usemap="#planetmap" />
​
<map name="planetmap">
<area id="venus" shape="circle" 
coords="180,139,14" 
alt="The planet Venus"
href="/example/hdom/venus.html" />
</map>
​
<p>"Venus" 的替代文本是：
<script type="text/javascript">
x=document.getElementById('venus');
document.write(x.alt);
</script>
</p>
​
</body>
</html>
​