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# CBCharacteristicWriteType

Values representing the possible write types to a characteristic’s value.

```
enum CBCharacteristicWriteType
```

## Overview

Characteristic write types have corresponding restrictions on the length of the data that you can write to a characteristic’s value. For the [`CBCharacteristicWriteType.withResponse`](/documentation/CoreBluetooth/CBCharacteristicWriteType/withResponse) write type’s restrictions, see the Bluetooth 4.0 specification, Volume 3, Part G, Sections 4.9.3–4. For the [`CBCharacteristicWriteType.withoutResponse`](/documentation/CoreBluetooth/CBCharacteristicWriteType/withoutResponse) write type restrictions, see the Bluetooth 4.0 specification, Volume 3, Part G, Sections 4.9.1–2.

> Tip:
> When you write with a response, you can write a characteristic value that’s longer than permitted when you write without a response.

## Topics

### Write Types

[`CBCharacteristicWriteWithResponse`](/documentation/CoreBluetooth/CBCharacteristicWriteType/withResponse)

Write a characteristic value, with a response from the peripheral to indicate whether the write was successful.

[`CBCharacteristicWriteWithoutResponse`](/documentation/CoreBluetooth/CBCharacteristicWriteType/withoutResponse)

Write a characteristic value, without any response from the peripheral to indicate whether the write was successful.

## Relationships

### Conforms To

[`BitwiseCopyable`](/documentation/Swift/BitwiseCopyable)

[`Hashable`](/documentation/Swift/Hashable)

[`Sendable`](/documentation/Swift/Sendable)

[`RawRepresentable`](/documentation/Swift/RawRepresentable)

[`Equatable`](/documentation/Swift/Equatable)

[`SendableMetatype`](/documentation/Swift/SendableMetatype)

---

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