deferred.then( doneFilter [, failFilter ] [, progressFilter ] ) Returns: Promise
Description: Add handlers to be called when the Deferred object is resolved, rejected, or still in progress.
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version added: 1.8deferred.then( doneFilter [, failFilter ] [, progressFilter ] )
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doneFilterType: Function()A function that is called when the Deferred is resolved.
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failFilterType: Function()An optional function that is called when the Deferred is rejected.
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progressFilterType: Function()An optional function that is called when progress notifications are sent to the Deferred.
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version added: 1.5, removed: 1.8deferred.then( doneCallbacks, failCallbacks )
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version added: 1.7, removed: 1.8deferred.then( doneCallbacks, failCallbacks [, progressCallbacks ] )
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doneCallbacksType: Function()A function, or array of functions, called when the Deferred is resolved.
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failCallbacksType: Function()A function, or array of functions, called when the Deferred is rejected.
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progressCallbacksType: Function()A function, or array of functions, called when the Deferred notifies progress.
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Prior to jQuery 1.8, the arguments could be a function or an array of functions.
For all signatures, the arguments can be null
if no callback of that type is desired. Alternatively, use .done()
, .fail()
or .progress()
to set only one type of callback without filtering status or values.
As of jQuery 1.8, the deferred.then()
method returns a new promise that can filter the status and values of a deferred through a function, replacing the now-deprecated deferred.pipe()
method. The doneFilter
and failFilter
functions filter the original deferred's resolved / rejected status and values. The progressFilter
function filters any calls to the original deferred's notify
or notifyWith
methods. These filter functions can return a new value to be passed along to the promise's .done()
or .fail()
callbacks, or they can return another observable object (Deferred, Promise, etc) which will pass its resolved / rejected status and values to the promise's callbacks. If the filter function used is null
, or not specified, the promise will be resolved or rejected with the same values as the original.
Callbacks are executed in the order they were added. Since deferred.then
returns a Promise, other methods of the Promise object can be chained to this one, including additional .then()
methods.
Examples:
Example: Since the jQuery.get
method returns a jqXHR object, which is derived from a Deferred object, we can attach handlers using the .then
method.
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Example: Filter the resolve value:
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Example: Filter reject value:
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Example: Chain tasks:
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