<html>
<head></head>
<body>
<button onclick="KeySend()">send ctrl + w</button>
</body>
<script>
function KeyPress(e) {
var evtobj = window.event ? event : e
if (evtobj.keyCode == 87 && evtobj.ctrlKey) alert("Ctrl+w");
}
function KeySend() {
var ke = new KeyboardEvent("keydown", {key: "w", keyCode: 87, ctrlKey: true, cancelable: true, bubbles: true});
document.dispatchEvent(ke);
}
document.onkeydown = KeyPress;
</script>
</html>