var postcodes = ["00-240", "80", "32", "90", "91"];

$('#test').keyup(function () {

    var val = this.value; 

    var m = $.map(postcodes, function (value, index) {

        var reg = new RegExp('^' + val + '.*$');

        return value.match(reg);

    });

    $('#msg').text(m.length && val.length ? 'VALID' : 'INVALID');

});