<!DOCTYPE html>
<html lang="en-US">
<body>
<div onmousedown="myFunction(event)">
<p> Click any <br>
0 = The left mouse button<br>
1 = The middle mouse button<br>
2 = The right mouse button<br>
</p>
</div>
<script>
function myFunction(event){
alert("You pressed button: "+ event.button);
}
</script> </body>
</html>