<!DOCTYPE html>
<html lang="en-US">
<body onkeydown="myFunction()">
<p>Focus this document and Press shift key.</p>
<p id="point"></p>
<script>
document.designMode = "on";
var x = document.getElementById("point");
// Try to replace "SelectAll" by "copy"
var support = "SelectAll";
function myFunction(){
if(event.keyCode == 16){
var state = document.queryCommandSupported(support);
if(state)
x.innerHTML = support +" is supported";
else
x.innerHTML = support +"is not supported";
}
}
</script> </body>
</html>