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# value

The data that the central reads from or writes to the peripheral.

```
var value: Data? { get set }
```

## Discussion

The value of this property depends on whether the request type is read or write. For read requests, the property is `nil,` and you should set it before responding to the remote central through the [`respond(to:withResult:)`](/documentation/CoreBluetooth/CBPeripheralManager/respond(to:withResult:)) method. For write requests, the value is the data to write to the characteristic’s value.

---

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