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WebHID API

{{DefaultAPISidebar("WebHID API")}} {{SeeCompatTable}} {{AvailableInWorkers("window_and_worker_except_shared")}} 

A Human Interface Device (HID) is a type of device that takes input from or provides output to humans. It also refers to the HID protocol, a standard for bi-directional communication between a host and a device that is designed to simplify the installation procedure. The HID protocol was originally developed for USB devices but has since been implemented over many other protocols, including Bluetooth.

Interfaces

Examples

You can connect to a device with the {{domxref("HID.requestDevice","requestDevice()")}}  method. In this case, we select from all the available devices.

const device = await navigator.hid.requestDevice({ filters: [] });
// A popup titled `... wants to connect to a HID Device` with `Cancel` and `Connect` buttons will show up with a device list to select from.
// Select one and click on `Connect` button. Then the device will be an array with the selected device in it.

We can retrieve all the devices the website has been granted access to previously and log the device names to the console.

let devices = await navigator.hid.getDevices();
devices.forEach((device) => {
  console.log(`HID: ${device.productName}`);
});

We can register event listeners for disconnection of any HID devices.

navigator.hid.addEventListener("disconnect", (event) => {
  console.log(`HID disconnected: ${event.device.productName}`);
  console.dir(event);
});
// For example, when my connected keyboard gets disconnected, the log in the console will show:
// HID disconnected: USB Keyboard
// {
//    bubbles: false
//    cancelBubble: false
//    cancelable: false
//    composed: false
//    currentTarget: HID {onconnect: null, ondisconnect: null}
//    defaultPrevented: false
//    device: HIDDevice {oninputreport: null, opened: false, vendorId: 6700, productId: 11555, productName: "USB Keyboard", …}
//    eventPhase: 0
//    isTrusted: true
//    path: []
//    returnValue: true
//    srcElement: HID {onconnect: null, ondisconnect: null}
//    target: HID {onconnect: null, ondisconnect: null}
//    timeStamp: 18176.600000023842
//    type: "disconnect"
// }

// The event above is an instance of the HIDConnectionEvent interface.

Specifications

{{Specifications}} 

Browser compatibility

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