Instance Method


Invoked when you retrieve a specified characteristic descriptor’s value.


optional func peripheral(_ peripheral: CBPeripheral, didUpdateValueFor descriptor: CBDescriptor, error: Error?)



The peripheral providing this information.


The characteristic descriptor whose value has been retrieved.


If an error occurred, the cause of the failure.


This method is invoked when your app calls the readValue(for:) method. If successful, the error parameter is nil. If unsuccessful, the error parameter returns the cause of the failure.

See Also

Retrieving Characteristic and Characteristic Descriptor Values

func peripheral(CBPeripheral, didUpdateValueFor: CBCharacteristic, error: Error?)

Invoked when you retrieve a specified characteristic’s value, or when the peripheral device notifies your app that the characteristic’s value has changed.

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