代码示例:(标识:bs_toast_close)
<!DOCTYPE html>
<html lang="en">
<head>
  <title>Bootstrap 实例</title>
  <meta charset="utf-8">
  <meta name="viewport" content="width=device-width, initial-scale=1">
  <link href="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/5.1.2/css/bootstrap.min.css" rel="stylesheet">
  <script src="https://cdn.bootcdn.net/ajax/libs/twitter-bootstrap/5.1.2/js/bootstrap.bundle.js"></script>
</head>
<body>

<div class="p-4">
  <h3>Toast 实例</h3>
  <p>Toast 类似警告框,它只在发生某些事情时显示几秒钟(即当用户单击按钮、提交表单等时)。</p>
  <p>在本例中,我们使用 .show 类来默认显示 toast。您可以通过单击 toast 标题内的关闭 (x) 图标来关闭它。</p>
  
  <div class="toast show">
    <div class="toast-header">
      <strong class="me-auto">Toast 标题</strong>
      <button type="button" class="btn-close" data-bs-dismiss="toast"></button>
    </div>
    <div class="toast-body">
      <p>toast 主体内的文本。</p>
    </div>
  </div>
</div>

</body>
</html>
运行结果: