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Alerts Bootstrap

Alerts in Bootstrap 4 are used to provide feedback messages to users. These can be success, warning, error, or informational messages. Alerts can be customized and closed by users if needed. Here’s a detailed explanation along with examples:

Basic Alert

To create a basic alert, use the .alert class along with contextual classes such as .alert-success, .alert-danger, .alert-warning, and .alert-info.

Example:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
  <title>Bootstrap 4 Alerts</title>
</head>
<body>

  <!-- Success Alert -->
  <div class="alert alert-success" role="alert">
    This is a success alert—check it out!
  </div>

  <!-- Danger Alert -->
  <div class="alert alert-danger" role="alert">
    This is a danger alert—check it out!
  </div>

  <!-- Warning Alert -->
  <div class="alert alert-warning" role="alert">
    This is a warning alert—check it out!
  </div>

  <!-- Info Alert -->
  <div class="alert alert-info" role="alert">
    This is an info alert—check it out!
  </div>

  <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
  <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.5.3/dist/umd/popper.min.js"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
</body>
</html>

Dismissible Alert

To make an alert dismissible, add the .alert-dismissible class along with a close button using the .close class.

Example:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
  <title>Dismissible Bootstrap 4 Alerts</title>
</head>
<body>

  <!-- Dismissible Success Alert -->
  <div class="alert alert-success alert-dismissible fade show" role="alert">
    This is a success alert—check it out!
    <button type="button" class="close" data-dismiss="alert" aria-label="Close">
      <span aria-hidden="true">&times;</span>
    </button>
  </div>

  <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
  <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.5.3/dist/umd/popper.min.js"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
</body>
</html>

Alert with Additional Content

Alerts can also contain additional HTML elements like headings, paragraphs, and dividers.

Example:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
  <title>Bootstrap 4 Alerts with Additional Content</title>
</head>
<body>

  <!-- Alert with Additional Content -->
  <div class="alert alert-warning" role="alert">
    <h4 class="alert-heading">Well done!</h4>
    <p>Aww yeah, you successfully read this important alert message. This example text is going to run a bit longer so that you can see how spacing within an alert works with this kind of content.</p>
    <hr>
    <p class="mb-0">Whenever you need to, be sure to use margin utilities to keep things nice and tidy.</p>
  </div>

  <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
  <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.5.3/dist/umd/popper.min.js"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
</body>
</html>

Colored Alerts

Bootstrap 4 also provides various color schemes for alerts to indicate the nature of the message.

Example:

<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <link href="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/css/bootstrap.min.css" rel="stylesheet">
  <title>Bootstrap 4 Colored Alerts</title>
</head>
<body>

  <!-- Primary Alert -->
  <div class="alert alert-primary" role="alert">
    This is a primary alert—check it out!
  </div>

  <!-- Secondary Alert -->
  <div class="alert alert-secondary" role="alert">
    This is a secondary alert—check it out!
  </div>

  <!-- Dark Alert -->
  <div class="alert alert-dark" role="alert">
    This is a dark alert—check it out!
  </div>

  <!-- Light Alert -->
  <div class="alert alert-light" role="alert">
    This is a light alert—check it out!
  </div>

  <script src="https://code.jquery.com/jquery-3.5.1.slim.min.js"></script>
  <script src="https://cdn.jsdelivr.net/npm/@popperjs/core@2.5.3/dist/umd/popper.min.js"></script>
  <script src="https://stackpath.bootstrapcdn.com/bootstrap/4.5.2/js/bootstrap.min.js"></script>
</body>
</html>

These examples cover the basic usage of alerts in Bootstrap 4, including making them dismissible and adding additional content. For more customization, you can always refer to the Bootstrap documentation.

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