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HID: requestDevice() method

{{securecontext_header}} {{APIRef("WebHID API")}} {{SeeCompatTable}} 

The requestDevice() method of the {{domxref("HID")}}  interface requests access to a HID device.

The user agent will present a permission dialog including a list of connected devices, and ask the user to select and grant permission to one of these devices.

Syntax

requestDevice(options)

Parameters

[!NOTE] The device filters are used to narrow the list of devices presented to the user. If no filters are present, all connected devices are shown. When one or more filters are included, a device is included if any filter matches. To match a filter, all of the rules included in that filter must match.

Return value

A {{jsxref("Promise")}}  that resolves with an array of connected {{domxref("HIDDevice")}}  objects that match the filters passed in.

Exceptions

Security

Transient user activation is required. The user has to interact with the page or a UI element in order for this feature to work.

Examples

Matching a device with all four filter rules

In the following example a HID device is requested that has a vendor ID of 0xABCD, product ID of 0x1234, usage page 0x0C and usage ID 0x01. Only devices that match all of these rules will be shown.

let requestButton = document.getElementById("request-hid-device");
requestButton.addEventListener("click", async () => {
  let device;
  try {
    const devices = await navigator.hid.requestDevice({
      filters: [
        {
          vendorId: 0xabcd,
          productId: 0x1234,
          usagePage: 0x0c,
          usage: 0x01,
        },
      ],
    });
    device = devices[0];
  } catch (error) {
    console.log("An error occurred.");
  }

  if (!device) {
    console.log("No device was selected.");
  } else {
    console.log(`HID: ${device.productName}`);
  }
});

An example with two filters

This next example includes two filters. Devices will be shown if they match either of these filters.

// Filter on devices with the Nintendo Switch Joy-Con USB Vendor/Product IDs.
const filters = [
  {
    vendorId: 0x057e, // Nintendo Co., Ltd
    productId: 0x2006, // Joy-Con Left
  },
  {
    vendorId: 0x057e, // Nintendo Co., Ltd
    productId: 0x2007, // Joy-Con Right
  },
];

// Prompt user to select a Joy-Con device.
const [device] = await navigator.hid.requestDevice({ filters });

Specifications

{{Specifications}} 

Browser compatibility

{{Compat}} 

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