Detect when input box filled by keyboard and when by barcode scanner.

Question

How I can programmatically detect when text input filled by typing on keyboard and when it filled automatically by bar-code scanner?

Answer 1

If you can set a prefix to your barcode scanner I suggests this (I changed a bit the Vitall code):

var BarcodeScanner = function(options) {
     this.initialize.call(this, options);
};
BarcodeScanner.prototype = {
    initialize: function(options) {
       $.extend(this._options,options);
       if(this._options.debug) console.log("BarcodeScanner: Initializing");
       $(this._options.eventObj).on({
          keydown: $.proxy(this._keydown, this),
       });
    },
    destroy: function() {
        $(this._options.eventObj).off("keyup",null,this._keyup);
        $(this._options.eventObj).off("keydown",null,this._keydown);
    },
    fire: function(str){
        if(this._options.debug) console.log("BarcodeScanner: Firing barcode event with string: "+str);
        $(this._options.fireObj).trigger('barcode',[str]);
    },
    isReading: function(){
        return this._isReading;
    },
    checkEvent: function(e){
        return this._isReading || (this._options.isShiftPrefix?e.shiftKey:!e.shiftKey) && e.which==this._options.prefixCode;
    },
    _options: {timeout: 600, prefixCode: 36, suffixCode: 13, minCode: 32, maxCode: 126, isShiftPrefix: false, debug: false, eventObj: document, fireObj: document},
    _isReading: false,
    _timeoutHandler: false,
    _inputString: '',
    _keydown: function (e) {
        if(this._input.call(this,e))
            return false;
    },
    _input: function (e) {
        if(this._isReading){
            if(e.which==this._options.suffixCode){
                //read end
                if(this._options.debug) console.log("BarcodeScanner: Read END");
                if (this._timeoutHandler) 
                    clearTimeout(this._timeoutHandler);
                this._isReading=false;
                this.fire.call(this,this._inputString);
                this._inputString='';
            }else{
                //char reading
                if(this._options.debug) console.log("BarcodeScanner: Char reading "+(e.which));
                if(e.which>=this._options.minCode && e.which<=this._options.maxCode)
                    this._inputString += String.fromCharCode(e.which);
            }
            return true;
        }else{
            if((this._options.isShiftPrefix?e.shiftKey:!e.shiftKey) && e.which==this._options.prefixCode){
                //start reading
                if(this._options.debug) console.log("BarcodeScanner: Start reading");
                this._isReading=true;
                this._timeoutHandler = setTimeout($.proxy(function () {
                    //read timeout
                    if(this._options.debug) console.log("BarcodeScanner: Read timeout");
                    this._inputString='';
                    this._isReading=false;
                    this._timeoutHandler=false;
                }, this), this._options.timeout);
                return true;
            }
        }
        return false;
    }
};

If you need you customize timeout, suffix, prefix, min/max ascii code readed:

new BarcodeScanner({timeout: 600, prefixKeyCode: 36, suffixKeyCode: 13, minKeyCode: 32, maxKeyCode: 126});

I also added the isShiftPrefix option to use for example the $ char as prefix with these options: new BarcodeScanner({prefixKeyCode: 52, isShiftPrefix: true});

This is a fiddle: https://jsfiddle.net/xmt76ca5/

Answer 2

$(window).ready(function(){

	//$("#bCode").scannerDetection();

	console.log('all is well');
	
	$(window).scannerDetection();
	$(window).bind('scannerDetectionComplete',function(e,data){
            console.log('complete '+data.string);
            $("#bCode").val(data.string);
        })
        .bind('scannerDetectionError',function(e,data){
            console.log('detection error '+data.string);
        })
        .bind('scannerDetectionReceive',function(e,data){
            console.log('Recieve');
            console.log(data.evt.which);
        })

        //$(window).scannerDetection('success');

<input id='bCode'type='text' value='barcode appears here'/>

Answer 3

The solution from Vitall only works fine if you already hit at least one key. If you don't the first character will be ignored (if(this._timeoutHandler) returns false and the char will not be appended).

If you want to begin scanning immediately you can use the following code:

var BarcodeScanerEvents = function() {
	this.initialize.apply(this, arguments);
};

BarcodeScanerEvents.prototype = {
	initialize : function() {
		$(document).on({
			keyup : $.proxy(this._keyup, this)
		});
	},
	_timeoutHandler : 0,
	_inputString : '',
	_keyup : function(e) {
		if (this._timeoutHandler) {
			clearTimeout(this._timeoutHandler);
		}
		this._inputString += String.fromCharCode(e.which);

		this._timeoutHandler = setTimeout($.proxy(function() {
			if (this._inputString.length <= 3) {
				this._inputString = '';
				return;
			}

			$(document).trigger('onbarcodescaned', this._inputString);

			this._inputString = '';

		}, this), 20);
	}
};

Answer 4

You can use a "onkeyup" event on that input box. If the event has triggered then you can called it "Input from Keyboard".

Answer 5

you can try following example, using jQuery plugin https://plugins.jquery.com/scannerdetection/

Its highly configurable, time based scanner detector. It can be used as solution for prefix/postfix based, time based barcode scanner.

Tutorial for usage and best practices, as well discussed about various Barcode Scanner Models and how to deal with it. http://a.kabachnik.info/jquery-scannerdetection-tutorial.html

$(window).ready(function(){

	//$("#bCode").scannerDetection();

	console.log('all is well');
	
	$(window).scannerDetection();
	$(window).bind('scannerDetectionComplete',function(e,data){
            console.log('complete '+data.string);
            $("#bCode").val(data.string);
        })
        .bind('scannerDetectionError',function(e,data){
            console.log('detection error '+data.string);
        })
        .bind('scannerDetectionReceive',function(e,data){
            console.log('Recieve');
            console.log(data.evt.which);
        })

        //$(window).scannerDetection('success');

<input id='bCode'type='text' value='barcode appears here'/>