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---
layout: docs
title: Alerts
description: Provide contextual feedback messages for typical user actions with the handful of available and flexible alert messages.
group: components
redirect_from:
- "/components/"
- "/docs/4.3/components/"
toc: true
---
## Examples
Alerts are available for any length of text, as well as an optional dismiss button. For proper styling, use one of the eight **required** contextual classes (e.g., `.alert-success`). For inline dismissal, use the [alerts JavaScript plugin](#dismissing).
{% capture example %}
{% for color in site.data.theme-colors %}
<div class="alert alert-{{ color.name }}" role="alert">
A simple {{ color.name }} alert—check it out!
</div>{% endfor %}
{% endcapture %}
{% include example.html content=example %}
{% include callout-warning-color-assistive-technologies.md %}
### Link color
Use the `.alert-link` utility class to quickly provide matching colored links within any alert.
{% capture example %}
{% for color in site.data.theme-colors %}
<div class="alert alert-{{ color.name }}" role="alert">
A simple {{ color.name }} alert with <a href="#" class="alert-link">an example link</a>. Give it a click if you like.
</div>{% endfor %}
{% endcapture %}
{% include example.html content=example %}
### Additional content
Alerts can also contain additional HTML elements like headings, paragraphs and dividers.
{% capture example %}
<div class="alert alert-success" 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>
{% endcapture %}
{% include example.html content=example %}
### Dismissing
Using the alert JavaScript plugin, it's possible to dismiss any alert inline. Here's how:
- Be sure you've loaded the alert plugin, or the compiled Bootstrap JavaScript.
- If you're building our JavaScript from source, it [requires `util.js`]({{ site.baseurl }}/docs/{{ site.docs_version }}/getting-started/javascript/#util). The compiled version includes this.
- Add a dismiss button and the `.alert-dismissible` class, which adds extra padding to the right of the alert and positions the `.close` button.
- On the dismiss button, add the `data-dismiss="alert"` attribute, which triggers the JavaScript functionality. Be sure to use the `<button>` element with it for proper behavior across all devices.
- To animate alerts when dismissing them, be sure to add the `.fade` and `.show` classes.
You can see this in action with a live demo:
{% capture example %}
<div class="alert alert-warning alert-dismissible fade show" role="alert">
<strong>Holy guacamole!</strong> You should check in on some of those fields below.
<button type="button" class="close" data-dismiss="alert" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
</div>
{% endcapture %}
{% include example.html content=example %}
## JavaScript behavior
### Triggers
Enable dismissal of an alert via JavaScript:
{% highlight js %}
var alertList = document.querySelectorAll('.alert')
alertList.forEach(function (alert) {
new bootstrap.Alert(alert)
})
{% endhighlight %}
Or with `data` attributes on a button **within the alert**, as demonstrated above:
{% highlight html %}
<button type="button" class="close" data-dismiss="alert" aria-label="Close">
<span aria-hidden="true">×</span>
</button>
{% endhighlight %}
Note that closing an alert will remove it from the DOM.
### Methods
You can create an alert instance with the alert constructor, for example:
{% highlight js %}
var myAlert = document.getElementById('myAlert')
var bsAlert = new bootstrap.Alert(myAlert)
{% endhighlight %}
This makes an alert listen for click events on descendant elements which have the `data-dismiss="alert"` attribute. (Not necessary when using the data-api's auto-initialization.)
| Method | Description |
| --- | --- |
| `close` | Closes an alert by removing it from the DOM. If the `.fade` and `.show` classes are present on the element, the alert will fade out before it is removed. |
| `dispose` | Destroys an element's alert. |
| `_getInstance` | *Static* method which allows you to get the alert instance associated to a DOM element, you can use it like this: `bootstrap.Alert._getInstance(alert)` |
{% highlight js %}
var alertNode = document.querySelector('.alert')
var alert = bootstrap.Alert._getInstance(alertNode)
alert.close()
{% endhighlight %}
### Events
Bootstrap's alert plugin exposes a few events for hooking into alert functionality.
| Event | Description |
| --- | --- |
| `close.bs.alert` | This event fires immediately when the <code>close</code> instance method is called. |
| `closed.bs.alert` | This event is fired when the alert has been closed (will wait for CSS transitions to complete). |
{% highlight js %}
var myAlert = document.getElementById('myAlert')
myAlert.addEventListener('closed.bs.alert', function () {
// do something…
})
{% endhighlight %}
|
