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BluetoothCharacteristicProperties - Web APIs 编辑

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The BluetoothCharacteristicProperties interface of the Web Bluetooth API provides the operations that are valid on the given BluetoothRemoteGATTCharacteristic. This interface is returned by calling BluetoothRemoteGATTCharacteristic.properties.

Properties

authenticatedSignedWritesRead only: Returns a boolean that is true if signed writing to the characteristic value is permitted.
broadcastRead only: Returns a boolean that is true if the broadcast of the characteristic value is permitted using the Server Characteristic Configuration Descriptor.
indicateRead only: Returns a boolean that is true if indications of the characteristic value with acknowledgement is permitted.
notifyRead only: Returns a boolean that is true if notifications of the characteristic value without acknowledgement is permitted.
readRead only: Returns a boolean that is true if the reading of the characteristic value is permitted.
reliableWriteRead only: Returns a boolean that is true if reliable writes to the characteristic is permitted.
writableAuxiliariesRead only: Returns a boolean that is true if reliable writes to the characteristic descriptor is permitted.
writeRead only: Returns a boolean that is true if the writing to the characteristic with response is permitted.
writeWithoutResponseRead only: 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',
      function(event) {
    console.log(`Received heart rate measurement: ${event.target.value}`);
  }
  await characteristic.startNotifications();
}