Deferred objeccts and their promises allow us to react to the conpletion of long-running tasks with a convenient syntax.
Object creation
Object creation
| Function |
Description |
| $.Deferred([setupFunction]) |
Returns a new deferred object. |
| $.when(deferreds) |
Returns a promise object to be resolved when the given deferred objecs are resolved. |
Methods of deferred objects
Methods of deferred objects
| Method |
Description |
| .resolve([args]) |
Sets the state of the object to resolved. |
| .resolveWith(context, [args]) |
Sets the state of the objec to resolved while making the keyword this refer to context within callbacks. |
| .rejectWith([args]) |
Sets the state of the object to rejected. |
| .rejectWith(context, [args]) |
Sets the state of the object to rejected while making the keyword this refer to context within callbacks. |
| .notify([args]) |
Executes any progress callbacks. |
| .notifyWith(context, [args]) |
Executes any progress callback while making the keyword this refer to context. |
| .promise([target]) |
Returns a promise object corresponding to this deferred object. |
Methods of promise objects
Methods of promise objects
| Method |
Description |
| .done(callback) |
Executes callback when the object is resolved. |
| .fail(callback) |
Executes callback when the object is rejected. |
| .always(callback) |
Executes callback when the object is resolved or rejected. |
| .then(doneCallbacks, failCallbacks) |
Executes doneCallbacks when the object is resolved, or failCallbacks when the object is rejected. |
| .progress(callback) |
Executes callback each time the object receives a progress notification. |
| .isRejected() |
Returns true if the object has been rejected. |
| .isResolved() |
Returns true if the object has been resolved. |
| .state() |
Returns ‘pending’, ‘resolved’, or ‘rejected’ depending on the current state. |
| .pipe([doneFilter], [failFilter]) |
Returns a new promise object which is resolved when the original promise is, optionally after filtering the object’s status through a function. |
峰间的云
