​x
 
<!DOCTYPE html>
<html>
<body>
​
<img src="/i/eg_planets.gif" 
width="145" height="126" 
usemap="#planetmap" />
​
<map name="planetmap">
<area id="venus" shape="circle" 
coords="124,58,8" 
alt="Venus"
href="/example/hdom/venus.html?id=venus" />
</map>
​
<p>单击按钮以显示“venus”区域的 href 属性的查询字符串部分。</p>
​
<button onclick="myFunction()">试一试</button>
​
<p id="demo"></p>
​
<script>
function myFunction() {
  var x = document.getElementById("venus").search;
  document.getElementById("demo").innerHTML = x;
}
</script>
​
</body>
</html>
​