ASCII control character html input text

Question

I\'m trying to process input from a barcode scanner in a javascript browser app. The scanner output is a string of characters, which also contains at least one Group Separator c

Answer 1

Inspired by Sebastian G, this option allows to catch all Alt + number codes. This doesn't work on IE however.

    var altvalue = '';
    document.getElementById('scanfield').addEventListener('keydown', function (e) {
        if (e.altKey) {
            if (e.keyCode !== 18 /* ALT key */) { altvalue += e.key; }
        }
    });

    document.getElementById('scanfield').addEventListener('keyup', function (e) {
        if (e.altKey === false && altvalue != '') {
            this.value += String.fromCharCode(parseInt(altvalue));
            altvalue = '';
        }
    });