The serialNumber
property of the NDEFReadingEvent
interface returns the serial number of the device, which is used for anti-collision and identification, or an empty string if no serial number is available.
A string containing the device's serial number.
This example shows how to create a convenience function that reads a single tag and then stops polling, saving battery life by cutting unneeded work. The example could easily be extended to time out after a given amount of milliseconds.
const ndefReader = new NDEFReader();
function read() {
return new Promise((resolve, reject) => {
const ctlr = new AbortController();
ctlr.signal.onabort = reject;
ndefReader.addEventListener("reading", event => {
ctlr.abort();
resolve(event);
}, { once: true });
ndefReader.scan({ signal: ctlr.signal }).catch(err => reject(err));
});
}
read().then(({ serialNumber }) => {
console.log(serialNumber);
});