ส่งค่าตัวแปลจาก input ใน Form ไปยัง modal ด้วย Enter

        <section class="page-section" id="contact">
            <div class="container">
                <h2 class="page-section-heading text-center text-uppercase text-secondary mb-0">REGISTER</h2>
                <div class="row">
                    <div class="col-lg-8 mx-auto">
                        <form  action="#exampleModal" method="post" id="new_group" onsubmit="submit_handler()">
                            <div class="control-group">
                                <div class="form-group floating-label-form-group controls mb-0 pb-2">
                                    <label class="fonts">เลขบัตรประชาชน</label>
                                    <input class="form-control fonts" id="card_id" type="text" name="card_id"placeholder="เลขบัตรประชาชน" required="required" minlength="13" maxlength="13" />                                   
                                </div>
                            </div>  
                        </form>
                    </div>
                </div>
            </div>
        </section>

<div class="modal" tabindex="-1" role="dialog" style="display:none" id="exampleModal">
  <div class="modal-dialog" role="document">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title">ข้อมูลผู้ป่วย</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 class="container">

      <?  
            echo  $_POST["card_id"];
      ?>
      <div class="modal-footer">
        <button type="button" class="btn btn-primary">Save changes</button>
        <button type="button" class="btn btn-secondary" data-dismiss="modal">Close</button>
      </div>
    </div>
  </div>
</div>

<script>

document.getElementById("card_id").addEventListener("keyup", function(event) {
   if (event.keyCode === 13) {
      document.getElementById("card_id").submit();
	return false;
    }
});
function submit_handler() {
  console.log('modal opened'); //send with ajax?
  $('#exampleModal').modal('show');
  event.preventDefault();
  
  return false;
}

</script>

document.getElementById("card_id").addEventListener("keypress", function(event) 
{
    if (event.keyCode === 13) 
    {       
    var  cardId = document.getElementById("card_id").value; 
    $('#exampleModal').modal('show');
    document.getElementById("bodyText").innerHTML = cardId;
     event.preventDefault();
    }
});