source/phone-format/phone-format.html

<!doctype html>
<html lang="en">

<head>
    <!-- Required meta tags -->
    <meta charset="utf-8">
    <meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
    <!-- Bootstrap CSS -->
    <link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/css/bootstrap.min.css" integrity="sha384-Gn5384xqQ1aoWXA+058RXPxPg6fy4IWvTNh0E263XmFcJlSAwiGgFAW/dAiS6JXm"
        crossorigin="anonymous">
    <title>Radio and Checkbox</title>
</head>

<body>
    <label>Phone</label>
    <input class="form-control phone" name="phone" type="text" required="true" />


    <!-- Optional JavaScript -->
    <!-- jQuery first, then Popper.js, then Bootstrap JS -->
    <script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN"
        crossorigin="anonymous"></script>
    <script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.12.9/umd/popper.min.js" integrity="sha384-ApNbgh9B+Y1QKtv3Rn7W3mgPxhU9K/ScQsAP7hUibX39j7fakFPskvXusvfa0b4Q"
        crossorigin="anonymous"></script>
    <script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js" integrity="sha384-JZR6Spejh4U02d8jOt6vLEHfe/JQGiRRSQQxSfFWpi1MquVdAyjUar5+76PVCmYl"
        crossorigin="anonymous"></script>

    <script type="text/javascript">
        $(function () {
            PhoneInput();
        });

        function PhoneInput() {

            $('input[type=text].phone').on('keydown', function (e) {
                -1 !== $.inArray(e.keyCode, [46, 8, 9, 27, 13, 110, 189]) || (/65|67|86|88/.test(e.keyCode) &&
                        (e.ctrlKey ===
                            true || e.metaKey === true)) && (!0 === e.ctrlKey || !0 === e.metaKey) || 35 <= e.keyCode &&
                    40 >= e.keyCode || (e.shiftKey || 48 > e.keyCode || 57 < e.keyCode) && (96 > e.keyCode ||
                        105 <
                        e.keyCode) && e.preventDefault();

            });

            $('input[type=text].phone').on('keyup', function (e) {
                var ph = this.value.replace(/\D/g, '').substring(0, 10);
                // Backspace and Delete keys
                var deleteKey = (e.keyCode == 8 || e.keyCode == 46);
                var len = ph.length;
                if (len == 0) {
                    ph = ph;
                } else if (len < 3) {
                    ph = '(' + ph;
                } else if (len == 3) {
                    ph = '(' + ph + (deleteKey ? '' : ') ');
                } else if (len < 6) {
                    ph = '(' + ph.substring(0, 3) + ') ' + ph.substring(3, 6);
                } else if (len == 6) {
                    ph = '(' + ph.substring(0, 3) + ') ' + ph.substring(3, 6) + (deleteKey ? '' : '-');
                } else {
                    ph = '(' + ph.substring(0, 3) + ') ' + ph.substring(3, 6) + '-' + ph.substring(6, 10);
                }
                this.value = ph;
            });
        }
    </script>
</body>

</html>