<html><body><img src="/i/eg_planets.gif"width="145" height="126"usemap="#planetmap" /><map name="planetmap"><area id="sun" shape="rect" coords="0,0,82,126" href="/example/hdom/sun.html" alt="Sun"><area id="mercury" shape="circle" coords="90,58,3" href="/example/hdom/mercur.html" alt="Mercury"><area id="venus" shape="circle" coords="124,58,8" href="/example/hdom/venus.html" alt="Venus"></map><br />第一个链接/地址的ID：<script>document.write(document.links[0].id);</script></body></html>