从 javascript 中的条件触发模态

Question

I have been painfully attempting to try and trigger a modal to fire, when a user writes more than 10 words in a textarea. I have tried the bootstrap documentation, 'Toggle AND 'Show' but they don't work. My console informs me that '.modal' isn't a correct function? but bootstrap informs me it is!

Basically my modal does not fire when the condition is met.

Here is my code:

HTML

  <form>
  <textarea placeholder="Would you like to leave a review?" maxlength="" id="textareaID"></textarea>
</form>


<div class="modal fade" id="exampleModal" tabindex="-1" aria-labelledby="exampleModalLabel" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalLabel">Modal title</h5>
        <button type="button" class="close" data-dismiss="modal" aria-label="Close">
          <span aria-hidden="true">&times;</span>
        </button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>
</div>
</div>
<script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" crossorigin="anonymous"></script>
<script src="/node_modules/jquery/dist/jquery.js"></script>
<script src="./script.js"></script>

JS

$('#textareaID').bind('input propertychange', function() {
  if (this.value.length > 10) {
    $(document).ready(function(){
    $('#exampleModal').modal('toggle');
  }
    $("#textareaID").val($("#textareaID").val().substring(0,20));
}
});

Answer 1

You can leverage .modal('show') .

Keep in mind that adding $(document).ready(fun... inside the binding is useless. You should be wrapping all your jQuery inside it.

Use the following:

 $(document).ready(function(){ $('#textareaID').on('input propertychange', function() { if ($('#textareaID').val().length > 10) { $('#exampleModal').modal('show'); $("#textareaID").val($("#textareaID").val().substring(0,20)); } }); });

 <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css" integrity="sha384-ggOyR0iXCbMQv3Xipma34MD+dH/1fQ784/j6cY/iJTQUOhcWr7x9JvoRxT2MZw1T" crossorigin="anonymous"><form> <textarea placeholder="Would you like to leave a review?" maxlength="" id="textareaID"></textarea> </form> <div class="modal fade" id="exampleModal" tabindex="-1" aria-labelledby="exampleModalLabel" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <h5 class="modal-title" id="exampleModalLabel">Modal title</h5> <button type="button" class="close" data-dismiss="modal" aria-label="Close"> <span aria-hidden="true">&times;</span> </button> </div> <div class="modal-body">... </div> <div class="modal-footer"> <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button> <button type="button" class="btn btn-primary">Save changes</button> </div> </div> </div> </div> </div> </div> <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js" integrity="sha384-DfXdz2htPH0lsSSs5nCTpuj/zy4C+OGpamoFVy38MVBnE+IbbVYUew+OrCXaRkfj" crossorigin="anonymous"></script> <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" crossorigin="anonymous"></script> <script src="/node_modules/jquery/dist/jquery.js"></script> <script src="./script.js"></script>

Answer 2

Use .modal('show') with proper syntax and it's working. It will display modal as soon as you enter 11th character. You can change the condition as per your need.

Regarding the use of $(document).ready() , you should wrap most javascript stuff in this function rather than using it in the if condition. It is just as a best practices. Not all elements would be available when the javascript is being executed.

 $(document).ready(function() { $('#textareaID').on('input propertychange', function() { if (this.value.length > 10) { $('#exampleModal').modal('show'); $("#textareaID").val($("#textareaID").val().substring(0, 20)); } }); });

 <link rel="stylesheet" href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" integrity="sha384-JcKb8q3iqJ61gNV9KGb8thSsNjpSL0n8PARn9HuZOnIxN0hoP+VmmDGMN5t9UJ0Z" crossorigin="anonymous"> <script src="https://cdnjs.cloudflare.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script> <script src="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/js/bootstrap.bundle.min.js" integrity="sha384-ho+j7jyWK8fNQe+A12Hb8AhRq26LrZ/JpcUGGOn+Y7RsweNrtN/tE3MoK7ZeZDyx" crossorigin="anonymous"></script> <form> <textarea placeholder="Would you like to leave a review?" maxlength="" id="textareaID"></textarea> </form> <div class="modal fade" id="exampleModal" tabindex="-1" aria-labelledby="exampleModalLabel" aria-hidden="true"> <div class="modal-dialog"> <div class="modal-content"> <div class="modal-header"> <h5 class="modal-title" id="exampleModalLabel">Modal title</h5> <button type="button" class="close" data-dismiss="modal" aria-label="Close"> <span aria-hidden="true">&times;</span> </button> </div> <div class="modal-body">... </div> <div class="modal-footer"> <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button> <button type="button" class="btn btn-primary">Save changes</button> </div> </div> </div> </div> </div> </div>