bootstrap loader in os code example

Example 1: bootstrap loader

<div class="spinner-border text-primary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-secondary" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-success" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-danger" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-warning" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-info" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-light" role="status">
  <span class="sr-only">Loading...</span>
</div>
<div class="spinner-border text-dark" role="status">
  <span class="sr-only">Loading...</span>
</div>

Example 2: how to add loader in bootstrap

<div class="spinner-border text-primary" 
    id="spinner"role="status">
    <span class="sr-only">Loading...</span>
</div>

Example 3: bootstrap loader

<button class="btn btn-primary" type="button" disabled>
  <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
  <span class="sr-only">Loading...</span>
</button>
<button class="btn btn-primary" type="button" disabled>
  <span class="spinner-border spinner-border-sm" role="status" aria-hidden="true"></span>
  Loading...
</button>