# .unload()

Categories: Events > Document Loading

## .unload( handler(eventObject) ) Returns: jQuery

Description: Bind an event handler to the "unload" JavaScript event.

- #### version added: 1.0.unload( handler(eventObject) )

  handler(eventObject)A function to execute when the event is triggered.

- #### version added: 1.4.3.unload( [eventData], handler(eventObject) )

  eventDataA map of data that will be passed to the event handler.

  handler(eventObject)A function to execute each time the event is triggered.

This method is a shortcut for `.bind('unload', handler)`.

The `unload` event is sent to the `window` element when the user navigates away from the page. This could mean one of many things. The user could have clicked on a link to leave the page, or typed in a new URL in the address bar. The forward and back buttons will trigger the event. Closing the browser window will cause the event to be triggered. Even a page reload will first create an `unload` event.

> The exact handling of the `unload` event has varied from version to version of browsers. For example, some versions of Firefox trigger the event when a link is followed, but not when the window is closed. In practical usage, behavior should be tested on all supported browsers, and contrasted with the proprietary `beforeunload` event.

Any `unload` event handler should be bound to the `window` object:

    $(window).unload(function() {
      alert('Handler for .unload() called.');
    });

After this code executes, the alert will be displayed whenever the browser leaves the current page. It is not possible to cancel the `unload` event with `.preventDefault()`. This event is available so that scripts can perform cleanup when the user leaves the page.

### Example:

#### To display an alert when a page is unloaded:

    $(window).unload( function () { alert("Bye now!"); } );