Bootstrap 4 Form Validation

Question

I'm a beginner with bootstrap and I have seen a lot of bootstrap 3 form validation plugins etc, but I haven't found any for bootstrap 4.

I'm trying to validate multiple forms, and here is my code:

I have tried to modify existing js, but I had no luck.

Here is the rendered form:

jsfiddle of the form

Answer 1

First I solved my issue with an external library like Jonathan Dion suggested. But recently I came across this :

Bootstrap v4.0 introduced their own form validation that you can still pair with backend php validation. From the Doc :

<form class="needs-validation" novalidate>
  <div class="form-row">
    <div class="col-md-4 mb-3">
      <label for="validationCustom01">First name</label>
      <input type="text" class="form-control" id="validationCustom01" placeholder="First name" value="Mark" required>
      <div class="valid-feedback">
        Looks good!
      </div>
      <div class="invalid-feedback">
        Doesn't look good!
      </div>
    </div>
  </div>
</div>

Then using JS :

<script>
// Example starter JavaScript for disabling form submissions if there are invalid fields
(function() {
  'use strict';
  window.addEventListener('load', function() {
    // Fetch all the forms we want to apply custom Bootstrap validation styles to
    var forms = document.getElementsByClassName('needs-validation');
    // Loop over them and prevent submission
    var validation = Array.prototype.filter.call(forms, function(form) {
      form.addEventListener('submit', function(event) {
        if (form.checkValidity() === false) {
          event.preventDefault();
          event.stopPropagation();
        }
        form.classList.add('was-validated');
      }, false);
    });
  }, false);
})();
</script>

This provides input border colorating and displays the valid / invalid feedback blocks according to the given pattern or properties. It is applied via CSS’s two pseudo-classes, :invalid and :valid. It applies to <input>, <select>, and <textarea> elements.