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Bootstrap/site/content/docs/5.2/components/alerts.md

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---
layout: docs
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title: Alerts
description: Provide contextual feedback messages for typical user actions with the handful of available and flexible alert messages.
group: components
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toc: true
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---
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## Examples
Alerts are available for any length of text, as well as an optional close 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).
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{{< example >}}
{{< alerts.inline >}}
{{- range (index $.Site.Data "theme-colors") }}
<div class="alert alert-{{ .name }}" role="alert">
A simple {{ .name }} alert—check it out!
</div>{{- end -}}
{{< /alerts.inline >}}
{{< /example >}}
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{{< callout info >}}
{{< partial "callout-warning-color-assistive-technologies.md" >}}
{{< /callout >}}
### Live example
Click the button below to show an alert (hidden with inline styles to start), then dismiss (and destroy) it with the built-in close button.
{{< example stackblitz_add_js="true" >}}
<div id="liveAlertPlaceholder"></div>
<button type="button" class="btn btn-primary" id="liveAlertBtn">Show live alert</button>
{{< /example >}}
We use the following JavaScript to trigger our live alert demo:
```js
const alertPlaceholder = document.getElementById('liveAlertPlaceholder')
const alert = (message, type) => {
const wrapper = document.createElement('div')
wrapper.innerHTML = [
`<div class="alert alert-${type} alert-dismissible" role="alert">`,
` <div>${message}</div>`,
' <button type="button" class="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>',
'</div>'
].join('')
alertPlaceholder.append(wrapper)
}
const alertTrigger = document.getElementById('liveAlertBtn')
if (alertTrigger) {
alertTrigger.addEventListener('click', () => {
alert('Nice, you triggered this alert message!', 'success')
})
}
```
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### Link color
Use the `.alert-link` utility class to quickly provide matching colored links within any alert.
{{< example >}}
{{< alerts.inline >}}
{{- range (index $.Site.Data "theme-colors") }}
<div class="alert alert-{{ .name }}" role="alert">
A simple {{ .name }} alert with <a href="#" class="alert-link">an example link</a>. Give it a click if you like.
</div>{{ end -}}
{{< /alerts.inline >}}
{{< /example >}}
### Additional content
Alerts can also contain additional HTML elements like headings, paragraphs and dividers.
{{< 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>
{{< /example >}}
### Icons
Similarly, you can use [flexbox utilities]({{< docsref "/utilities/flex" >}}) and [Bootstrap Icons]({{< param icons >}}) to create alerts with icons. Depending on your icons and content, you may want to add more utilities or custom styles.
{{< example >}}
<div class="alert alert-primary d-flex align-items-center" role="alert">
<svg xmlns="http://www.w3.org/2000/svg" class="bi bi-exclamation-triangle-fill flex-shrink-0 me-2" viewBox="0 0 16 16" role="img" aria-label="Warning:">
<path d="M8.982 1.566a1.13 1.13 0 0 0-1.96 0L.165 13.233c-.457.778.091 1.767.98 1.767h13.713c.889 0 1.438-.99.98-1.767L8.982 1.566zM8 5c.535 0 .954.462.9.995l-.35 3.507a.552.552 0 0 1-1.1 0L7.1 5.995A.905.905 0 0 1 8 5zm.002 6a1 1 0 1 1 0 2 1 1 0 0 1 0-2z"/>
</svg>
<div>
An example alert with an icon
</div>
</div>
{{< /example >}}
Need more than one icon for your alerts? Consider using more Bootstrap Icons and making a local SVG sprite like so to easily reference the same icons repeatedly.
{{< example >}}
<svg xmlns="http://www.w3.org/2000/svg" style="display: none;">
<symbol id="check-circle-fill" viewBox="0 0 16 16">
<path d="M16 8A8 8 0 1 1 0 8a8 8 0 0 1 16 0zm-3.97-3.03a.75.75 0 0 0-1.08.022L7.477 9.417 5.384 7.323a.75.75 0 0 0-1.06 1.06L6.97 11.03a.75.75 0 0 0 1.079-.02l3.992-4.99a.75.75 0 0 0-.01-1.05z"/>
</symbol>
<symbol id="info-fill" viewBox="0 0 16 16">
<path d="M8 16A8 8 0 1 0 8 0a8 8 0 0 0 0 16zm.93-9.412-1 4.705c-.07.34.029.533.304.533.194 0 .487-.07.686-.246l-.088.416c-.287.346-.92.598-1.465.598-.703 0-1.002-.422-.808-1.319l.738-3.468c.064-.293.006-.399-.287-.47l-.451-.081.082-.381 2.29-.287zM8 5.5a1 1 0 1 1 0-2 1 1 0 0 1 0 2z"/>
</symbol>
<symbol id="exclamation-triangle-fill" viewBox="0 0 16 16">
<path d="M8.982 1.566a1.13 1.13 0 0 0-1.96 0L.165 13.233c-.457.778.091 1.767.98 1.767h13.713c.889 0 1.438-.99.98-1.767L8.982 1.566zM8 5c.535 0 .954.462.9.995l-.35 3.507a.552.552 0 0 1-1.1 0L7.1 5.995A.905.905 0 0 1 8 5zm.002 6a1 1 0 1 1 0 2 1 1 0 0 1 0-2z"/>
</symbol>
</svg>
<div class="alert alert-primary d-flex align-items-center" role="alert">
<svg class="bi flex-shrink-0 me-2" role="img" aria-label="Info:"><use xlink:href="#info-fill"/></svg>
<div>
An example alert with an icon
</div>
</div>
<div class="alert alert-success d-flex align-items-center" role="alert">
<svg class="bi flex-shrink-0 me-2" role="img" aria-label="Success:"><use xlink:href="#check-circle-fill"/></svg>
<div>
An example success alert with an icon
</div>
</div>
<div class="alert alert-warning d-flex align-items-center" role="alert">
<svg class="bi flex-shrink-0 me-2" role="img" aria-label="Warning:"><use xlink:href="#exclamation-triangle-fill"/></svg>
<div>
An example warning alert with an icon
</div>
</div>
<div class="alert alert-danger d-flex align-items-center" role="alert">
<svg class="bi flex-shrink-0 me-2" role="img" aria-label="Danger:"><use xlink:href="#exclamation-triangle-fill"/></svg>
<div>
An example danger alert with an icon
</div>
</div>
{{< /example >}}
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### Dismissing
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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.
- Add a [close button]({{< docsref "/components/close-button" >}}) and the `.alert-dismissible` class, which adds extra padding to the right of the alert and positions the close button.
- On the close button, add the `data-bs-dismiss="alert"` attribute, which triggers the JavaScript functionality. Be sure to use the `<button>` element with it for proper behavior across all devices.
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- To animate alerts when dismissing them, be sure to add the `.fade` and `.show` classes.
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You can see this in action with a live demo:
{{< example >}}
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<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="btn-close" data-bs-dismiss="alert" aria-label="Close"></button>
</div>
{{< /example >}}
{{< callout warning >}}
When an alert is dismissed, the element is completely removed from the page structure. If a keyboard user dismisses the alert using the close button, their focus will suddenly be lost and, depending on the browser, reset to the start of the page/document. For this reason, we recommend including additional JavaScript that listens for the `closed.bs.alert` event and programmatically sets `focus()` to the most appropriate location in the page. If you're planning to move focus to a non-interactive element that normally does not receive focus, make sure to add `tabindex="-1"` to the element.
{{< /callout >}}
## CSS
### Variables
{{< added-in "5.2.0" >}}
As part of Bootstrap's evolving CSS variables approach, alerts now use local CSS variables on `.alert` for enhanced real-time customization. Values for the CSS variables are set via Sass, so Sass customization is still supported, too.
{{< scss-docs name="alert-css-vars" file="scss/_alert.scss" >}}
### Sass variables
{{< scss-docs name="alert-variables" file="scss/_variables.scss" >}}
### Sass mixin
Used in combination with `$theme-colors` to create contextual modifier classes for our alerts.
{{< scss-docs name="alert-variant-mixin" file="scss/mixins/_alert.scss" >}}
### Sass loop
Loop that generates the modifier classes with the `alert-variant()` mixin.
{{< scss-docs name="alert-modifiers" file="scss/_alert.scss" >}}
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## JavaScript behavior
### Initialize
Initialize elements as alerts
```js
const alertList = document.querySelectorAll('.alert')
const alerts = [...alertList].map(element => new bootstrap.Alert(element))
```
{{< callout info >}}
For the sole purpose of dismissing an alert, it isn't necessary to initialize the component manually via the JS API. By making use of `data-bs-dismiss="alert"`, the component will be initialized automatically and properly dismissed.
See the [triggers](#triggers) section for more details.
{{< /callout >}}
### Triggers
{{% js-dismiss "alert" %}}
**Note that closing an alert will remove it from the DOM.**
### Methods
You can create an alert instance with the alert constructor, for example:
```js
const bsAlert = new bootstrap.Alert('#myAlert')
```
This makes an alert listen for click events on descendant elements which have the `data-bs-dismiss="alert"` attribute. (Not necessary when using the data-apis auto-initialization.)
{{< bs-table >}}
| 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. (Removes stored data on the DOM element) |
| `getInstance` | Static method which allows you to get the alert instance associated to a DOM element. For example: `bootstrap.Alert.getInstance(alert)`. |
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| `getOrCreateInstance` | Static method which returns an alert instance associated to a DOM element or create a new one in case it wasn't initialized. You can use it like this: `bootstrap.Alert.getOrCreateInstance(element)`. |
{{< /bs-table >}}
Basic usage:
```js
const alert = bootstrap.Alert.getOrCreateInstance('#myAlert')
alert.close()
```
### Events
Bootstrap's alert plugin exposes a few events for hooking into alert functionality.
{{< bs-table >}}
| Event | Description |
| --- | --- |
| `close.bs.alert` | Fires immediately when the `close` instance method is called. |
| `closed.bs.alert` | Fired when the alert has been closed and CSS transitions have completed. |
{{< /bs-table >}}
```js
const myAlert = document.getElementById('myAlert')
myAlert.addEventListener('closed.bs.alert', event => {
// do something, for instance, explicitly move focus to the most appropriate element,
// so it doesn't get lost/reset to the start of the page
// document.getElementById('...').focus()
})
```