# .unload()

## unload ( handler(eventObject) ) Returns: jQuery version added: 1.0

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

## unload ( eventData, handler(eventObject) ) Returns: jQuery version added: 1.4.3

- eventData
  Type: Object
  A plain object of data that will be passed to the event handler.

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

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

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 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.

## Examples:

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

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