gistfile1.js

    getBytes    : function (bytes, type) {
        var value = bytes;

        if (!isNaN(value)) {
            switch (type) {
            case 'Kb':
                value *= 1024;
                break;
            case 'Mb':
                value *= Math.pow(1024, 2);
                break;
            case 'Gb':
                value *= Math.pow(1024, 3);
                break;
            default:
                break;
            }

            return value;
        } else {
            return null;
        }
    }