<html>
<body>
<p id="demo">Click the button to get the value of the value of the button's first attribute.</p>
<button onclick="myFunction()">Try it</button>
<script>
function myFunction()
{
var btn=document.getElementsByTagName("BUTTON")[0];
var x=document.getElementById("demo");
x.innerHTML=btn.attributes[0].value;
}
</script>
<p><strong>Note:</strong> In Internet Explorer 8 and earlier, the attributes property will return a collection of all possible attributes for the element, and will, in this example, display the value of a different attribute than "onclick".</p>
</body>
</html>