BluetoothCharacteristicProperties

Secure contextLimited availability

The BluetoothCharacteristicProperties interface of the Web Bluetooth API provides the operations that are valid on the given BluetoothRemoteGATTCharacteristic.

This interface is returned by calling properties.

Instance properties

• authenticatedSignedWrites Read only Experimental
  • : Returns a boolean that is true if signed writing to the characteristic value is permitted.
• broadcast Read only Experimental
  • : Returns a boolean that is true if the broadcast of the characteristic value is permitted using the Server Characteristic Configuration Descriptor.
• indicate Read only Experimental
  • : Returns a boolean that is true if indications of the characteristic value with acknowledgement is permitted.
• notify Read only Experimental
  • : Returns a boolean that is true if notifications of the characteristic value without acknowledgement is permitted.
• read Read only Experimental
  • : Returns a boolean that is true if the reading of the characteristic value is permitted.
• reliableWrite Read only Experimental
  • : Returns a boolean that is true if reliable writes to the characteristic is permitted.
• writableAuxiliaries Read only Experimental
  • : Returns a boolean that is true if reliable writes to the characteristic descriptor is permitted.
• write Read only Experimental
  • : Returns a boolean that is true if the writing to the characteristic with response is permitted.
• writeWithoutResponse Read only Experimental
  • : Returns a boolean that is true if the writing to the characteristic without response is permitted.

Examples

The following example shows how tell if a GATT characteristic supports value change notifications.

let device = await navigator.bluetooth.requestDevice({
  filters: [{ services: ["heart_rate"] }],
});
let gatt = await device.gatt.connect();
let service = await gatt.getPrimaryService("heart_rate");
let characteristic = await service.getCharacteristic("heart_rate_measurement");
if (characteristic.properties.notify) {
  characteristic.addEventListener(
    "characteristicvaluechanged",
    async (event) => {
      console.log(`Received heart rate measurement: ${event.target.value}`);
    },
  );
  await characteristic.startNotifications();
}

Specifications

Browser compatibility