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

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);
	}
};