USB: requestDevice() method

{{APIRef("WebUSB API")}}{{SeeCompatTable}}{{SecureContext_Header}}{{AvailableInWorkers}}

The requestDevice() method of the {{domxref("USB")}} interface returns a {{jsxref("Promise")}} that resolves with an instance of {{domxref("USBDevice")}} if the specified device is found. Calling this function triggers the user agent's pairing flow.

Syntax

requestDevice(options)

Parameters

• options
  • : An object that sets options for selecting an appropriate device. The available options are:
    • filters
      • : An array of filter objects for possible devices you would like to pair. Each filter object can have the following properties:
        • vendorId
        • productId
        • classCode
        • subclassCode
        • protocolCode
        • serialNumber

Return value

A {{JSxRef("Promise")}} that resolves with an instance of {{DOMxRef("USBDevice")}}.

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

The following example looks for one of two USB devices. Notice that two product IDs are specified. Both are passed to requestDevice(). This triggers a user-agent flow that prompts the user to select a device for pairing. Only the selected device is passed to then().

The number of filters does not specify the number of devices shown by the user agent. For example, if only a USB device with product ID 0xa800 is found, then only one device will be listed by the user agent. On the other hand if the user agent finds two of the first listed device and one of the second, then all three devices will be listed.

const filters = [
  { vendorId: 0x1209, productId: 0xa800 },
  { vendorId: 0x1209, productId: 0xa850 },
];
navigator.usb
  .requestDevice({ filters })
  .then((usbDevice) => {
    console.log(`Product name: ${usbDevice.productName}`);
  })
  .catch((e) => {
    console.error(`There is no device. ${e}`);
  });

Specifications

{{Specifications}}

Browser compatibility

{{Compat}}