USB: requestDevice() method
Limited availability
This feature is not Baseline because it does not work in some of the most widely-used browsers.
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
Secure context: This feature is available only in secure contexts (HTTPS), in some or all supporting browsers.
Note: This feature is available in Web Workers.
The requestDevice()
method of the USB
interface returns a Promise
that resolves with an instance of
USBDevice
if the specified device is found. Calling this function
triggers the user agent's pairing flow.
Syntax
requestDevice(filters)
Parameters
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
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
Specification |
---|
WebUSB API # ref-for-dom-usb-requestdevice④ |
Browser compatibility
BCD tables only load in the browser