Bootstrap 5 fornece uma maneira fácil de criar mensagens de alerta predefinidas:
Os alertas são criados com a classe .alert, seguida por uma das classes contextuais:
.alert-success
.alert-info
.alert-warning
.alert-danger
.alert-primary
.alert-secondary
.alert-light
.alert-dark<div class="alert alert-success">
<strong>Success!</strong> Indicates a successful or positive action.
</div>Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Alerts</h2>
<p>Alerts are created with the .alert class, followed by a contextual color classes:</p>
<div class="alert alert-success">
<strong>Success!</strong> This alert box could indicate a successful or positive action.
</div>
<div class="alert alert-info">
<strong>Info!</strong> This alert box could indicate a neutral informative change or action.
</div>
<div class="alert alert-warning">
<strong>Warning!</strong> This alert box could indicate a warning that might need attention.
</div>
<div class="alert alert-danger">
<strong>Danger!</strong> This alert box could indicate a dangerous or potentially negative action.
</div>
<div class="alert alert-primary">
<strong>Primary!</strong> Indicates an important action.
</div>
<div class="alert alert-secondary">
<strong>Secondary!</strong> Indicates a slightly less important action.
</div>
<div class="alert alert-dark">
<strong>Dark!</strong> Dark grey alert.
</div>
<div class="alert alert-light">
<strong>Light!</strong> Light grey alert.
</div>
</div>
</body>
</html>
Adicione a classe .alert-link a qualquer link dentro da caixa de alerta para criar "links coloridos correspondentes":
<div class="alert alert-success">
<strong>Success!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Alert Links</h2>
<p>Add the alert-link class to any links inside the alert box to create "matching colored links".</p>
<div class="alert alert-success">
<strong>Success!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-info">
<strong>Info!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-warning">
<strong>Warning!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-danger">
<strong>Danger!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-primary">
<strong>Primary!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-secondary">
<strong>Secondary!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-dark">
<strong>Dark!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
<div class="alert alert-light">
<strong>Light!</strong> You should <a href="#" class="alert-link">read this message</a>.
</div>
</div>
</body>
</html>
Para fechar a mensagem de alerta, adicione um .alert-dismissible classe para o contêiner de alerta. Em seguida, adicione class="btn-close" e data-bs-dismiss="alert" para um link ou elemento de botão (quando você clica nele, a caixa de alerta será desaparecer).
<div class="alert alert-success alert-dismissible">
<button
type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Success!</strong> This alert box could indicate a successful or
positive action.
</div>Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Alerts</h2>
<p>The button with class="btn-close" and data-bs-dismiss="alert" is used to close the alert box.</p>
<p>The alert-dismissible class aligns the button to the right.</p>
<div class="alert alert-success alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Success!</strong> This alert box could indicate a successful or positive action.
</div>
<div class="alert alert-info alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Info!</strong> This alert box could indicate a neutral informative change or action.
</div>
<div class="alert alert-warning alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Warning!</strong> This alert box could indicate a warning that might need attention.
</div>
<div class="alert alert-danger alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Danger!</strong> This alert box could indicate a dangerous or potentially negative action.
</div>
<div class="alert alert-primary alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Primary!</strong> Indicates an important action.
</div>
<div class="alert alert-secondary alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Secondary!</strong> Indicates a slightly less important action.
</div>
<div class="alert alert-dark alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Dark!</strong> Dark grey alert.
</div>
<div class="alert alert-light alert-dismissible">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Light!</strong> Light grey alert.
</div>
</div>
</body>
</html>
As classes .fade e .show adicionam um efeito de esmaecimento quando fechando a mensagem de alerta:
<div class="alert alert-danger
alert-dismissible fade show">Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Animated Alerts</h2>
<p>The .fade and .show classes adds a fading effect when closing the alert message.</p>
<div class="alert alert-success alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Success!</strong> This alert box could indicate a successful or positive action.
</div>
<div class="alert alert-info alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Info!</strong> This alert box could indicate a neutral informative change or action.
</div>
<div class="alert alert-warning alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Warning!</strong> This alert box could indicate a warning that might need attention.
</div>
<div class="alert alert-danger alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Danger!</strong> This alert box could indicate a dangerous or potentially negative action.
</div>
<div class="alert alert-primary alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Primary!</strong> Indicates an important action.
</div>
<div class="alert alert-secondary alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Secondary!</strong> Indicates a slightly less important action.
</div>
<div class="alert alert-dark alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Dark!</strong> Dark grey alert.
</div>
<div class="alert alert-light alert-dismissible fade show">
<button type="button" class="btn-close" data-bs-dismiss="alert"></button>
<strong>Light!</strong> Light grey alert.
</div>
</div>
</body>
</html>