Name
Window.onunload: the handler invoked when the browser leaves a page â DOM Level 0:
Synopsis
Function onunload
Description
The onunload property of a
Window specifies an event-handler function that is invoked when the
browser âunloadsâ a document in preparation for loading a new
one.
The initial value of this property is a function that contains
the semicolon-separated JavaScript statements specified by the
onunload attribute of the
<body> or <frameset> tags.
The onunload event handler
enables you to perform any necessary cleanup of the browser state
before a new document is loaded.
The onunload( ) handler is
invoked when the user has instructed the browser to leave the
current page and move somewhere else. Therefore, it is usually
inappropriate to delay the loading of the desired new page by
popping up dialog boxes (with Window.confirm( ) or Window.prompt( ), for example) from an
onunload event handler.
See Also
Window.onload; Chapter 17
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