Instance Method

willAccessValueForKey:

Provides support for key-value observing access notification.

Declaration

- (void)willAccessValueForKey:(NSString *)key;

Parameters

key

The name of one of the receiver's properties.

Discussion

See didAccessValueForKey: for more details. You can invoke this method with the key value of nil to ensure that a fault has been fired, as illustrated by the following example.

[aManagedObject willAccessValueForKey:nil];

See Also

Supporting Key-Value Observing

+ automaticallyNotifiesObserversForKey:

Returns a Boolean value that indicates whether the receiver provides automatic support for key-value observing change notifications for the given key.

- didAccessValueForKey:

Provides support for key-value observing access notification.

- observationInfo

Returns the observation info of the managed object.

- setObservationInfo:

Sets the observation info of the managed object.

- didChangeValueForKey:

Provides an opportunity to respond when a value of a given property has changed.

- didChangeValueForKey:withSetMutation:usingObjects:

Provides an opportunity to respond when a change was made to a specified to-many relationship.

- willChangeValueForKey:

Provides an opportunity to respond when a value of a given property is about to change.

- willChangeValueForKey:withSetMutation:usingObjects:

Provides an opportunity to respond when a change is about to be made to a specified to-many relationship.

Beta Software

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