<!DOCTYPE html>
<html>
<body>
<h3>A demonstration of how to access a BUTTON element</h3>
<p>Click to disable the BUTTON element:</p>
<button type="button" id="myBtn" onclick="myFunction()">Try it</button>
<p id="demo"></p>
<script>
function myFunction() {
var x = document.getElementById("myBtn");
x.disabled = true;
}
</script>
</body>
</html>