Instance Method


Discovers the specified characteristics of a service.


func discoverCharacteristics(_ characteristicUUIDs: [CBUUID]?, for service: CBService)



An array of CBUUID objects that you are interested in. Each CBUUID object represents a UUID that identifies the type of a characteristic you want to discover.


The service whose characteristics you want to discover.


You can provide an array of CBUUID objects—representing characteristic UUIDs— in the characteristicUUIDs parameter. When you do, the peripheral returns only the characteristics of the service that match the provided UUIDs. If the characteristicUUIDs parameter is nil, this method returns all characteristics of the service.

When the peripheral discovers one or more characteristics of the specified service, it calls the peripheral(_:didDiscoverCharacteristicsFor:error:) method of its delegate object. After the peripheral discovers the service’s characteristics, you can access them through the service’s characteristics property.

See Also

Discovering Characteristics and Descriptors

func discoverDescriptors(for: CBCharacteristic)

Discovers the descriptors of a characteristic.