## .unload( handler )Returns: jQuery version deprecated: 1.8, removed: 3.0

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

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

  - handler
    Type: Function( Event eventObject )
    A function to execute when the event is triggered.

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

  - eventData
    Type: Anything
    A plain object of data that will be passed to the event handler.
  - handler
    Type: Function( Event eventObject )
    A function to execute each time the event is triggered.

This method is a shortcut for `.on( "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 similar `beforeunload` event.

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

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    $( window ).unload(function() {  return "Handler for .unload() called.";});

This event is available so that scripts can perform cleanup when the user leaves the page. Most browsers will ignore calls to `alert()`, `confirm()` and `prompt()` inside the event handler. The string you return may be used in a confirmation dialog, but not all browsers support this. It is not possible to cancel the `unload` event with `.preventDefault()`.

### Additional Notes:

- As the `.unload()` method is just a shorthand for `.on( "unload", handler )`, detaching is possible using `.off( "unload" )`.

## Example:

To display an alert when a page is unloaded:

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