<!DOCTYPE html>
<html>
<body>

<p>The removeEventListener() method is not supported Internet Explorer 8 and earlier versions.</p>

<p>This example demonstrates a solution that will work for all browsers.</p>

<p>This document has an onmousemove event handler attached with the addEventListener() method, that displays a random number every time you move your mouse in this document.</p>

<p>Click the button to remove the event handler.</p>

<button onclick="removeHandler()" id="myBtn">Try it</button>

<p id="demo"></p>

<script>
if (document.addEventListener) {
    document.addEventListener("mousemove", myFunction);
} else if (document.attachEvent) {
    document.attachEvent("onmousemove", myFunction);
}

function myFunction() {
    document.getElementById("demo").innerHTML = Math.random();
}

function removeHandler() {
    if (document.removeEventListener) {
        document.removeEventListener("mousemove", myFunction);
    } else if (document.detachEvent) {
        document.detachEvent("onmousemove", myFunction);
    }
}
</script>

</body>
</html>