ipi-jquery/exemples/validation-de-formulaires-bootstrap/script.js

$('#registerInputUsername1')
.change(function(e) {
    var inputUsername = $(this);
    var username = inputUsername.val();
    var re = /^[A-Za-z][A-Za-z0-9_]+$/;
    var isUsernameValid = username.match(re);
    if(! isUsernameValid) {
        inputUsername
        .addClass('is-invalid')
        .removeClass('is-valid');
        return;
    }

    $.get(
        'http://localhost:3001/username-check?username=' + username,
        function(response) {
            console.log(response.success)
            if(response.success) {
                inputUsername
                .addClass('is-valid')
                .removeClass('is-invalid');
            }
            else {
                inputUsername
                .addClass('is-invalid')
                .removeClass('is-valid');
                return;
            }
                
        }
    );
});

var onglets = $('#onglets li a');

onglets.click(function(e) {
    var link = $(this);
    onglets.removeClass('active');
    link.addClass('active');
    var idPanneau = link.data('tab-id');
    $('.tab').hide();
    $('#' + idPanneau).show();
});