Value Event

Fired when a characteristic or descriptor value is received from the server.

Syntax

type TValueEvent = procedure (
  Sender: TObject;
  const ServiceId: String;
  const CharacteristicId: String;
  const DescriptorId: String;
  const Uuid: String;
  const Description: String;
  Value: String;
  ValueB: TBytes
) of Object;

property OnValue: TValueEvent read FOnValue write FOnValue;

Remarks

This event is fired to signify that a value has been received for a characteristic or descriptor. The DescriptorId parameter will be empty string if the value is for a characteristic.

Uuid and Description are the UUID and Bluetooth SIG user-friendly name (if one is defined) of the characteristic or descriptor.

There are three scenarios which can cause this event to fire:

• The server has responded to a read request for a characteristic.
• The server has responded to a read request for a descriptor.
• The server has sent an updated value for a subscribed characteristic.

Whenever a value is received for a characteristic or descriptor, the value that the platform has cached for it is updated as well. You can read the cached value for a characteristic using CharacteristicCachedValue, or for a descriptor using DescriptorCachedValue.

Refer to the ReadValue and/or Subscribe methods for more information.