Let's have a look at the code which will create a confirmation dialog box with an alert of what users click in the dialog box.
  1. <html>
  3. <body>
  4. <p>Click the button to display a confirmation box.</p>
  5. <button onclick="myBox()">Click it</button>
  6. <p id="function"></p>
  7. <script>
  8. function myBox() {
  9. var x;
  10. var y = confirm("Click a button!");
  11. if (y == true) {
  12. x = "You clicked OK button!";
  13. } else {
  14. x = "You clicked Cancel button!";
  15. }
  16. document.getElementById("function").innerHTML = x;
  17. }
  18. </script>
  19. </body>
  21. </html>
Output
After clicking the button the dialog box will be shown.
When you click the OK or Cancel button the following output will be shown.