Scan Detector

Detect barcode scanner and keyboard input events separately in your web or electronJS application with ease.

install

$ npm i scan-detector --save

Quick usage

const ScanDetector = require("scan-detector");

let detector = ScanDetector();

detector.attach();

document.addEventListener("scanner", (e) => {
  // handle scan code
});

document.addEventListener("keyboard", (e) => {
  // handle keyboard input
});

detector.detach();

Options

let sd = ScanDetector({ element: document, minCodeLength: 4 });

Option	Type	Default	Description
element	html element	document	html element to attach and listen for inputs
prefix	array (char codes)	[]	these characters will be discarded
suffix	array (char codes)	[9, 13]	possible end characters, will be discarded
avgCharTime	number (ms)	30	average time between each scanner keydown event
minCodeLength	number	6	min length of scanned code
customEncoder	function(number keyCode)	null	will be called on each keydown event
onScanFinish	function(string scanCode)	null	will be called when scan is finished
preventDefault	bool	false	prevent default keydown behavior
stopPropagation	bool	false	stops event propagation
debugMode	bool	false	logs each keydown event in console

Methods

setOptions(options):

seta detector options.

getOptions():

returns detector options.

attach():

attach detector to the element, it will listen to keydown event in the element.

detach():

detach detector from element.

Example

const ScanDetector = require("scan-detector");

let input = document.getElementById("text_input");

let detector = ScanDetector({
  element: document,
  avgCharTime: 30,
  minCodeLength: 6,
  customEncoder: (event) => {
    return event.key;
  },
  onScanFinish: (code) => {
    return [...code.matchAll(/Alt([0-9]{3})/g)].reduce((t, v) => {
      return (t += String.fromCharCode(+v[1]));
    }, "");
  },
});

detector.attach();

document.addEventListener("scanner", (e) => {
  input.value = e.detail;
});

document.addEventListener("keyboard", (e) => {
  console.log(e);
});