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The user agent has found an update and is fetching it, or is downloading the resources listed by the manifest for the first time.

Property of apis/appcache/ApplicationCacheapis/appcache/ApplicationCache


var result = window.applicationCache.ondownloading;
window.applicationCache.ondownloading = value;

Return Value

Returns an object of type nullnull


If more than one event is triggered and the downloading event is included, the next events may include progress, error, cached, or updateready. Alternatively, you could use an anonymous delegate function such as

object.ondownloading = function (e) { … }

where e is the cached event.

Related specifications

W3C ApplicationCache Specification
W3C Editor’s Draft


  • Microsoft Developer Network: Article