Window.confirm()

The Window.confirm() method displays a modal dialog with an optional message and two buttons: OK and Cancel.

result = window.confirm(message);

message

A string you want to display in the alert dialog.

A boolean indicating whether OK (true) or Cancel (false) was selected. If a browser is ignoring in-page dialogs, then the returned value is always false.

if (window.confirm("Do you really want to leave?")) {
  window.open("exit.html", "Thanks for Visiting!");
}

Produces:

The following text is shared between this article, DOM:window.prompt and DOM:window.alert Dialog boxes are modal windows — they prevent the user from accessing the rest of the program's interface until the dialog box is closed. For this reason, you should not overuse any function that creates a dialog box (or modal window). Regardless, there are good reasons to avoid using dialog boxes for confirmation.

• window.alert()
• window.prompt()