Tryit Editor v1.8

Source Code:
<!DOCTYPE html> <html> <head> <script> var myWindow; function openWin() { myWindow = window.open("","","width=400,height=200"); } function closeWin() { if (myWindow) { myWindow.close(); } } function checkWin() { if (!myWindow) { document.getElementById("msg").innerHTML="'myWindow' has never been opened!"; } else { if (myWindow.closed) { document.getElementById("msg").innerHTML="'myWindow' has been closed!"; } else { document.getElementById("msg").innerHTML="'myWindow' has not been closed!"; } } } </script> </head> <body> <button onclick="openWin()">Open "myWindow"</button> <button onclick="closeWin()">Close "myWindow"</button> <br><br> <button onclick="checkWin()">Has "myWindow" been closed?</button> <br><br> <div id="msg"></div> </body> </html>
Result:
W3Schools.com - Try it yourself