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web api interface

Magnetometer

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Secure contextLimited availability

The Magnetometer interface of the Sensor APIs provides information about the magnetic field as detected by the device’s primary magnetometer sensor.

To use this sensor, the user must grant permission to the 'magnetometer' device sensor through the Permissions API. In addition, this feature may be blocked by a Permissions Policy set on your server.

Constructor

Instance properties

  • x Read only Experimental
    • : Returns a double containing the magnetic field around the device’s x axis.
  • y Read only Experimental
    • : Returns a double containing the magnetic field around the device’s y axis.
  • z Read only Experimental
    • : Returns a double containing the magnetic field around the device’s z axis.

Instance methods

Magnetometer doesn’t have own methods. However, it inherits methods from its parent interfaces, Sensor and EventTarget.

Events

Magnetometer doesn’t have own events. However, it inherits events from its parent interface, Sensor.

Example

The magnetometer is typically read in the reading event callback. In the example below this occurs sixty times a second.

let magSensor = new Magnetometer({ frequency: 60 });

magSensor.addEventListener("reading", (e) => {
  console.log(`Magnetic field along the X-axis ${magSensor.x}`);
  console.log(`Magnetic field along the Y-axis ${magSensor.y}`);
  console.log(`Magnetic field along the Z-axis ${magSensor.z}`);
});
magSensor.start();

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.