معین

var myModal = document.getElementById('myModal')
var myInput = document.getElementById('myInput')

myModal.addEventListener('shown.bs.modal', function () {
  myInput.focus()
})

<div class="modal" tabindex="-1">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title">Modal title</h5>
        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        <p>Modal body text goes here.</p>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

<!-- Button trigger modal -->
<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#exampleModal">
  Launch demo modal
</button>

<!-- Modal -->
<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="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Save changes</button>
      </div>
    </div>
  </div>
</div>

<!-- Button trigger modal -->
<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#staticBackdrop">
  Launch static backdrop modal
</button>

<!-- Modal -->
<div class="modal fade" id="staticBackdrop" data-bs-backdrop="static" data-bs-keyboard="false" tabindex="-1" aria-labelledby="staticBackdropLabel" aria-hidden="true">
  <div class="modal-dialog">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="staticBackdropLabel">Modal title</h5>
        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        ...
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Understood</button>
      </div>
    </div>
  </div>
</div>

<!-- Scrollable modal -->
<div class="modal-dialog modal-dialog-scrollable">
  ...
</div>

<!-- Vertically centered modal -->
<div class="modal-dialog modal-dialog-centered">
  ...
</div>

<!-- Vertically centered scrollable modal -->
<div class="modal-dialog modal-dialog-centered modal-dialog-scrollable">
  ...
</div>

<div class="modal-body">
  <h5>Popover in a modal</h5>
  <p>This <a href="#" role="button" class="btn btn-secondary popover-test" title="Popover title" data-bs-content="Popover body content is set in this attribute.">button</a> triggers a popover on click.</p>
  <hr>
  <h5>Tooltips in a modal</h5>
  <p><a href="#" class="tooltip-test" title="Tooltip">This link</a> and <a href="#" class="tooltip-test" title="Tooltip">that link</a> have tooltips on hover.</p>
</div>

<div class="modal-body">
  <div class="container-fluid">
    <div class="row">
      <div class="col-md-4">.col-md-4</div>
      <div class="col-md-4 ms-auto">.col-md-4 .ms-auto</div>
    </div>
    <div class="row">
      <div class="col-md-3 ms-auto">.col-md-3 .ms-auto</div>
      <div class="col-md-2 ms-auto">.col-md-2 .ms-auto</div>
    </div>
    <div class="row">
      <div class="col-md-6 ms-auto">.col-md-6 .ms-auto</div>
    </div>
    <div class="row">
      <div class="col-sm-9">
        Level 1: .col-sm-9
        <div class="row">
          <div class="col-8 col-sm-6">
            Level 2: .col-8 .col-sm-6
          </div>
          <div class="col-4 col-sm-6">
            Level 2: .col-4 .col-sm-6
          </div>
        </div>
      </div>
    </div>
  </div>
</div>

<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#exampleModal" data-bs-whatever="@mdo">Open modal for @mdo</button>
<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#exampleModal" data-bs-whatever="@fat">Open modal for @fat</button>
<button type="button" class="btn btn-primary" data-bs-toggle="modal" data-bs-target="#exampleModal" data-bs-whatever="@getbootstrap">Open modal for @getbootstrap</button>

<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">New message</h5>
        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        <form>
          <div class="mb-3">
            <label for="recipient-name" class="col-form-label">Recipient:</label>
            <input type="text" class="form-control" id="recipient-name">
          </div>
          <div class="mb-3">
            <label for="message-text" class="col-form-label">Message:</label>
            <textarea class="form-control" id="message-text"></textarea>
          </div>
        </form>
      </div>
      <div class="modal-footer">
        <button type="button" class="btn btn-secondary" data-bs-dismiss="modal">Close</button>
        <button type="button" class="btn btn-primary">Send message</button>
      </div>
    </div>
  </div>
</div>

var exampleModal = document.getElementById('exampleModal')
exampleModal.addEventListener('show.bs.modal', function (event) {
  // Button that triggered the modal
  var button = event.relatedTarget
  // Extract info from data-bs-* attributes
  var recipient = button.getAttribute('data-bs-whatever')
  // If necessary, you could initiate an AJAX request here
  // and then do the updating in a callback.
  //
  // Update the modal's content.
  var modalTitle = exampleModal.querySelector('.modal-title')
  var modalBodyInput = exampleModal.querySelector('.modal-body input')

  modalTitle.textContent = 'New message to ' + recipient
  modalBodyInput.value = recipient
})

<div class="modal fade" id="exampleModalToggle" aria-hidden="true" aria-labelledby="exampleModalToggleLabel" tabindex="-1">
  <div class="modal-dialog modal-dialog-centered">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalToggleLabel">Modal 1</h5>
        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        Show a second modal and hide this one with the button below.
      </div>
      <div class="modal-footer">
        <button class="btn btn-primary" data-bs-target="#exampleModalToggle2" data-bs-toggle="modal">Open second modal</button>
      </div>
    </div>
  </div>
</div>
<div class="modal fade" id="exampleModalToggle2" aria-hidden="true" aria-labelledby="exampleModalToggleLabel2" tabindex="-1">
  <div class="modal-dialog modal-dialog-centered">
    <div class="modal-content">
      <div class="modal-header">
        <h5 class="modal-title" id="exampleModalToggleLabel2">Modal 2</h5>
        <button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>
      </div>
      <div class="modal-body">
        Hide this modal and show the first with the button below.
      </div>
      <div class="modal-footer">
        <button class="btn btn-primary" data-bs-target="#exampleModalToggle" data-bs-toggle="modal">Back to first</button>
      </div>
    </div>
  </div>
</div>
<a class="btn btn-primary" data-bs-toggle="modal" href="#exampleModalToggle" role="button">Open first modal</a>

<div class="modal" tabindex="-1" aria-labelledby="..." aria-hidden="true">
  ...
</div>

<div class="modal-dialog modal-xl">...</div>
<div class="modal-dialog modal-lg">...</div>
<div class="modal-dialog modal-sm">...</div>

<!-- Full screen modal -->
<div class="modal-dialog modal-fullscreen-sm-down">
  ...
</div>

$modal-inner-padding:               $spacer;

$modal-footer-margin-between:       .5rem;

$modal-dialog-margin:               .5rem;
$modal-dialog-margin-y-sm-up:       1.75rem;

$modal-title-line-height:           $line-height-base;

$modal-content-color:               null;
$modal-content-bg:                  $white;
$modal-content-border-color:        rgba($black, .2);
$modal-content-border-width:        $border-width;
$modal-content-border-radius:       $border-radius-lg;
$modal-content-inner-border-radius: subtract($modal-content-border-radius, $modal-content-border-width);
$modal-content-box-shadow-xs:       $box-shadow-sm;
$modal-content-box-shadow-sm-up:    $box-shadow;

$modal-backdrop-bg:                 $black;
$modal-backdrop-opacity:            .5;
$modal-header-border-color:         $border-color;
$modal-footer-border-color:         $modal-header-border-color;
$modal-header-border-width:         $modal-content-border-width;
$modal-footer-border-width:         $modal-header-border-width;
$modal-header-padding-y:            $modal-inner-padding;
$modal-header-padding-x:            $modal-inner-padding;
$modal-header-padding:              $modal-header-padding-y $modal-header-padding-x; // Keep this for backwards compatibility

$modal-sm:                          300px;
$modal-md:                          500px;
$modal-lg:                          800px;
$modal-xl:                          1140px;

$modal-fade-transform:              translate(0, -50px);
$modal-show-transform:              none;
$modal-transition:                  transform .3s ease-out;
$modal-scale-transform:             scale(1.02);

@each $breakpoint in map-keys($grid-breakpoints) {
  $infix: breakpoint-infix($breakpoint, $grid-breakpoints);
  $postfix: if($infix != "", $infix + "-down", "");

  @include media-breakpoint-down($breakpoint) {
    .modal-fullscreen#{$postfix} {
      width: 100vw;
      max-width: none;
      height: 100%;
      margin: 0;

      .modal-content {
        height: 100%;
        border: 0;
        @include border-radius(0);
      }

      .modal-header {
        @include border-radius(0);
      }

      .modal-body {
        overflow-y: auto;
      }

      .modal-footer {
        @include border-radius(0);
      }
    }
  }
}

<button type="button" data-bs-toggle="modal" data-bs-target="#myModal">Launch modal</button>

<button type="button" class="btn-close" data-bs-dismiss="modal" aria-label="Close"></button>

<button type="button" class="btn-close" data-bs-dismiss="modal" data-bs-target="#my-modal" aria-label="Close"></button>

var myModal = new bootstrap.Modal(document.getElementById('myModal'), options)

var myModal = new bootstrap.Modal(document.getElementById('myModal'), {
  keyboard: false
})

myModal.toggle()

myModal.show()

var modalToggle = document.getElementById('toggleMyModal') // relatedTarget
myModal.show(modalToggle)

myModal.hide()

myModal.handleUpdate()

myModal.dispose()

var myModalEl = document.getElementById('myModal')
var modal = bootstrap.Modal.getInstance(myModalEl) // Returns a Bootstrap modal instance

var myModalEl = document.querySelector('#myModal')
var modal = bootstrap.Modal.getOrCreateInstance(myModalEl) // Returns a Bootstrap modal instance

var myModalEl = document.getElementById('myModal')
myModalEl.addEventListener('hidden.bs.modal', function (event) {
  // do something...
})