Restrict special characters with javascript / jQuery

no-special-characters.js

<script>
    $(document).ready(function() {
        $('textarea').bind('keypress', function (event) {
            // Allow for regular characters and include these special few:
            // comma, period, explanation point, new line
            var regex = new RegExp("^[a-zA-Z0-9\r\n\.\,\!\ ]+$");
            var key = String.fromCharCode(!event.charCode ? event.which : event.charCode);
            if (!regex.test(key)) {
                event.preventDefault();
                return false;
            }
        });
    });
</script>