close window exxternal javascript code example

Example 1: javascript close window

<!DOCTYPE html>
<html>
<body>

<button onclick="openWin()">Open "myWindow"</button>
<button onclick="closeWin()">Close "myWindow"</button>

<script>
var myWindow;

function openWin() {
  myWindow = window.open("", "myWindow", "width=200,height=100");
  myWindow.document.write("<p>This is 'myWindow'</p>");
}

function closeWin() {
  myWindow.close();
}
</script>

</body>
</html>

Example 2: on window close give alert javascript

let disableConfirmation = false;
window.addEventListener('beforeunload', event => {
  const confirmationText = 'Are you sure?';
  if (!disableConfirmation) {
    event.returnValue = confirmationText; // Gecko, Trident, Chrome 34+
    return confirmationText;              // Gecko, WebKit, Chrome <34
  } else {
    // Set flag back to false, just in case
    // user stops loading page after clicking a link.
    disableConfirmation = false;
  }
});

After Confimation if you want to send any ajax request and you have used jquery
 $(window).on('unload', function() {
   // async: false will make the AJAX synchronous in case you're using jQuery
   axios
     .get('ajax_url')
     .then(response => {});
 });

And if no jquery is used you can use navigator, it require navigator library

navigator.sendBeacon(url, data);