<!DOCTYPE html>
<html>
<body>
<img id="planets" src="planets.gif" width="145" height="126">
<map name="planetmap">
<area id="venus" shape="circle" coords="124,58,8" alt="The planet venus" href="venus.htm">
</map>
<p id="demo">It is not possible to click on the "venus" area in the image-map, because the the image does not have a usemap.</p>
<p>Click the button to set the value of the usemap attribute of the image to "#planetmap".</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction() {
var x = document.getElementById("planets").useMap = "#planetmap";
document.getElementById("demo").innerHTML = "The usemap is set, and the venus link now works!";
}
</script>
</body>
</html>