Way to override exit button event in browser?

[Vinnie123]

In my application, sometimes users accidentally click the "exit" button in the far right corner of the browser window and lose all of their unsaved work. Is there a way to prevent the window from automatically closing, and instead prompt the user if we wants to actually close it?

[acoder]

You can use onbeforeunload. An enhancement would be to first check if any changes have been made. If they have then ask for confirmation, otherwise just let the user close the browser.

[akristensen]

An example of how to do this is:

<script language="javascript">
    //Make sure the user is warned that there is data that has not been saved.
    function UnloadTrigger() {
        var boolChallengeClose = true;
        //do checks here to see if you want to prompt them to close window
        if (boolChallengeClose) {
            // Return a string from this function so a popup box will be presented to the user.
            // The popup box is part of the window.onbeforeunload routine.
            return ("Something needs to be saved.\nDo it! :)  ");
        }
    }
    window.onbeforeunload = UnloadTrigger;
</script>
 

[Vinnie123]

Thanks guys. That's just what I needed.

For those reading this post in the future, I found a good example after reading the previous replies to my original question. It can be found here:

http://www.4guysfromrolla.com/demos/...nloadDemo1.htm