Component aliases
<b-form-textarea>
can also be used via the following aliases:
<b-textarea>
Note: component aliases are only available when importing all of BootstrapVue or using the component group plugin.
Create multi-line text inputs with support for auto height sizing, minimum and maximum number of rows, and contextual states.
<template>
<div>
<b-form-textarea
id="textarea"
v-model="text"
placeholder="Enter something..."
rows="3"
max-rows="6"
></b-form-textarea>
<pre class="mt-3 mb-0">{{ text }}</pre>
</div>
</template>
<script>
export default {
data() {
return {
text: ''
}
}
}
</script>
<!-- b-form-textarea.vue -->
Set text height using the size
prop to sm
or lg
for small or large respectively.
To control width, place the input inside standard Bootstrap grid column.
<b-container fluid>
<b-row>
<b-col sm="2">
<label for="textarea-small">Small:</label>
</b-col>
<b-col sm="10">
<b-form-textarea
id="textarea-small"
size="sm"
placeholder="Small textarea"
></b-form-textarea>
</b-col>
</b-row>
<b-row class="mt-2">
<b-col sm="2">
<label for="textarea-default">Default:</label>
</b-col>
<b-col sm="10">
<b-form-textarea
id="textarea-default"
placeholder="Default textarea"
></b-form-textarea>
</b-col>
</b-row>
<b-row class="mt-2">
<b-col sm="2">
<label for="textarea-large">Large:</label>
</b-col>
<b-col sm="10">
<b-form-textarea
id="textarea-large"
size="lg"
placeholder="Large textarea"
></b-form-textarea>
</b-col>
</b-row>
</b-container>
<!-- b-form-textarea-sizes.vue -->
To set the height of <b-form-textarea>
, set the rows
prop to the desired number of rows. If no value is provided to rows
, then it will default to 2
(the browser default and minimum acceptable value). Setting it to null or a value below 2 will result in the default of 2
being used.
<div>
<b-form-textarea
id="textarea-rows"
placeholder="Tall textarea"
rows="8"
></b-form-textarea>
</div>
<!-- b-form-textarea-rows.vue -->
Some web browsers will allow the user to re-size the height of the textarea. To disable this feature, set the no-resize
prop to true
.
<div>
<b-form-textarea
id="textarea-no-resize"
placeholder="Fixed height textarea"
rows="3"
no-resize
></b-form-textarea>
</div>
<!-- b-form-textarea-no-resize.vue -->
<b-form-textarea>
can also automatically adjust its height (text rows) to fit the content, even as the user enters or deletes text. The height of the textarea will either grow or shrink to fit the content (grow to a maximum of max-rows
or shrink to a minimum of rows
).
To set the initial minimum height (in rows), set the rows
prop to the desired number of lines (or leave it at the default of 2
), And then set maximum rows that the text area will grow to (before showing a scrollbar) by setting the max-rows
prop to the maximum number of lines of text.
To make the height sticky
(i.e. never shrink), set the no-auto-shrink
prop to true
. The no-auto-shrink
props has no effect if max-rows
is not set or is equal to or less than rows
.
Note that the resize handle of the textarea (if supported by the browser) will automatically be disabled in auto-height mode.
<b-container fluid>
<b-row>
<b-col sm="2">
<label for="textarea-auto-height">Auto height:</label>
</b-col>
<b-col sm="10">
<b-form-textarea
id="textarea-auto-height"
placeholder="Auto height textarea"
rows="3"
max-rows="8"
></b-form-textarea>
</b-col>
</b-row>
<b-row class="mt-2">
<b-col sm="2">
<label for="textarea-no-auto-shrink">No auto-shrink:</label>
</b-col>
<b-col sm="10">
<b-form-textarea
id="textarea-no-auto-shrink"
placeholder="Auto height (no-shrink) textarea"
rows="3"
max-rows="8"
no-auto-shrink
></b-form-textarea>
</b-col>
</b-row>
</b-container>
<!-- b-form-textarea-auto-height.vue -->
Auto-height works by computing the resulting height via CSS queries, hence the input has to be in document (DOM) and visible (not hidden via display: none
). Initial height is computed on mount. If the browser client supports IntersectionObserver
(either natively or via a polyfill), <b-form-textarea>
will take advantage of this to determine when the textarea becomes visible and will then compute the height. Refer to the Browser support section on the getting started page.
Bootstrap includes validation styles for valid
and invalid
states on most form controls.
Generally speaking, you'll want to use a particular state for specific types of feedback:
false
(denotes invalid state) is great for when there's a blocking or required field. A user must fill in this field properly to submit the form.true
(denotes valid state) is ideal for situations when you have per-field validation throughout a form and want to encourage a user through the rest of the fields.null
Displays no validation state (neither valid nor invalid)To apply one of the contextual state icons on <b-form-textarea>
, set the state
prop to false
(for invalid), true
(for valid), or null
(no validation state).
<template>
<div>
<b-form-textarea
id="textarea-state"
v-model="text"
:state="text.length >= 10"
placeholder="Enter at least 10 characters"
rows="3"
></b-form-textarea>
</div>
</template>
<script>
export default {
data() {
return {
text: ''
}
}
}
</script>
<!-- b-form-textarea-state.vue -->
Using these contextual states to denote the state of a form control only provides a visual, color-based indication, which will not be conveyed to users of assistive technologies - such as screen readers - or to colorblind users.
Ensure that an alternative indication of state is also provided. For instance, you could include a hint about state in the form control's <label>
text itself, or by providing an additional help text block.
aria-invalid
attributeWhen <b-form-textarea>
has an invalid contextual state (i.e. state is false
) you may also want to set the prop aria-invalid
to true
, or one of the supported values:
false
: No errors (default)true
or 'true'
: The value has failed validation.'grammar'
: A grammatical error has been detected.'spelling'
A spelling error has been detected.If the state
prop is set to false
, and the aria-invalid
prop is not explicitly set, <b-form-textarea>
will automatically set the aria-invalid
attribute to 'true'
.
<b-form-textarea>
optionally supports formatting by passing a function reference to the formatter
prop.
Formatting (when a formatter function is supplied) occurs when the control's native input
and change
events fire. You can use the boolean prop lazy-formatter
to restrict the formatter function to being called on the control's native blur
event.
The formatter
function receives two arguments: the raw value
of the input element, and the native event
object that triggered the format (if available).
The formatter
function should return the formatted value as a string.
Formatting does not occur if a formatter
is not provided.
<template>
<div>
<b-form-group
class="mb-0"
label="Textarea with formatter (on input)"
label-for="textarea-formatter"
description="We will convert your text to lowercase instantly"
>
<b-form-textarea
id="textarea-formatter"
v-model="text1"
placeholder="Enter your text"
:formatter="formatter"
></b-form-textarea>
</b-form-group>
<p style="white-space: pre-line"><b>Value:</b> {{ text1 }}</p>
<b-form-group
class="mb-0"
label="Textarea with lazy formatter (on blur)"
label-for="textarea-lazy"
description="This one is a little lazy!"
>
<b-form-textarea
id="textarea-lazy"
v-model="text2"
placeholder="Enter your text"
lazy-formatter
:formatter="formatter"
></b-form-textarea>
</b-form-group>
<p class="mb-0" style="white-space: pre-line"><b>Value:</b> {{ text2 }}</p>
</div>
</template>
<script>
export default {
data() {
return {
text1: '',
text2: ''
}
},
methods: {
formatter(value) {
return value.toLowerCase()
}
}
}
</script>
<!-- b-form-textarea-formatter.vue -->
Note: With non-lazy formatting, if the cursor is not at the end of the input value, the cursor may jump to the end after a character is typed. You can use the provided event object and the event.target
to access the native input's selection methods and properties to control where the insertion point is. This is left as an exercise for the reader.
If you want to have <b-form-textarea readonly>
elements in your form styled as plain text, set the plaintext
prop (no need to set readonly
as it will be set automatically) to remove the default form field styling and preserve the correct text size, margin, padding and height.
<template>
<div>
<b-form-textarea id="textarea-plaintext" plaintext :value="text"></b-form-textarea>
</div>
</template>
<script>
export default {
data() {
return {
text: "This is some text.\nIt is read only and doesn't look like an input."
}
}
}
</script>
<!-- b-form-textarea-plaintext.vue -->
v-model
modifiersVue does not officially support .lazy
, .trim
, and .number
modifiers on the v-model
of custom component based inputs, and may generate a bad user experience. Avoid using Vue's native modifiers.
To get around this, <b-form-textarea>
has three boolean props trim
, number
, and lazy
which emulate the native Vue v-model
modifiers .trim
and .number
and .lazy
respectively. The lazy
prop will update the v-model on change
/blur
events.
Notes:
number
prop takes precedence over the trim
prop (i.e. trim
will have no effect when number
is set).number
prop, and if the value can be parsed as a number (via parseFloat
) it will return a value of type Number
to the v-model
, otherwise the original input value is returned as type String
. This is the same behaviour as the native .number
modifier.trim
and number
modifier props do not affect the value returned by the input
or change
events. These events will always return the string value of the content of <textarea>
after optional formatting (which may not match the value returned via the v-model
update
event, which handles the modifiers).As an alternative to the lazy
modifier prop, <b-form-textarea>
optionally supports debouncing user input, updating the v-model
after a period of idle time from when the last character was entered by the user (or a change
event occurs). If the user enters a new character (or deletes characters) before the idle timeout expires, the timeout is re-started.
To enable debouncing, set the prop debounce
to any integer greater than zero. The value is specified in milliseconds. Setting debounce
to 0
will disable debouncing.
Note: debouncing will not occur if the lazy
prop is set.
<template>
<div>
<b-form-textarea v-model="value" debounce="500" rows="3" max-rows="5"></b-form-textarea>
<pre class="mt-2 mb-0">{{ value }}</pre>
</div>
</template>
<script>
export default {
data() {
return {
value: ''
}
}
}
</script>
<!-- b-form-textarea-debounce.vue -->
When the autofocus
prop is set on <b-form-textarea>
, the textarea will be auto-focused when it is inserted (i.e. mounted) into the document or re-activated when inside a Vue <keep-alive>
component. Note that this prop does not set the autofocus
attribute on the textarea, nor can it tell when the textarea becomes visible.
All native events (other than the custom input
and change
events) are supported, without the need for the .native
modifier.
The custom input
and change
events receive a single argument of the current value
(after any formatting has been applied), and are triggered by user interaction.
The custom update
event is passed the input value, and is emitted whenever the v-model
needs updating (it is emitted before input
, change
. and blur
as needed).
You can always access the native input
and change
events by using the .native
modifier.
<b-form-textarea>
exposes several of the native input element's properties and methods on the component reference (i.e. assign a ref
to your <b-form-textarea ref="foo" ...>
and use this.$refs['foo'].propertyName
or this.$refs['foo'].methodName(...)
).
Property | Notes |
---|---|
.selectionStart | Read/Write |
.selectionEnd | Read/Write |
.selectionDirection | Read/Write |
.validity | Read only |
.validationMessage | Read only |
.willValidate | Read only |
Method | Notes |
---|---|
.focus() | Focus the input |
.blur() | Remove focus from the input |
.select() | Selects all text within the input |
.setSelectionRange() | |
.setRangeText() | |
.setCustomValidity() | |
.checkValidity() | |
.reportValidity() |
Refer to https://developer.mozilla.org/en-US/docs/Web/API/HTMLInputElement for more information on these methods and properties. Support will vary based on input type.
<b-form-textarea>
Component aliases
<b-form-textarea>
Properties
<b-form-textarea>
v-model
<b-form-textarea>
Events
<b-form-textarea>
can also be used via the following aliases:
<b-textarea>
Note: component aliases are only available when importing all of BootstrapVue or using the component group plugin.
Property (Click to sort Ascending) | Type | Default | Description |
---|---|---|---|
id | String | Used to set the 'id' attribute on the rendered content, and used as the base to generate any additional element IDs as needed | |
name | String | Sets the value of the 'name' attribute on the form control | |
disabled | Boolean | When set to 'true', disables the component's functionality and places it in a disabled state | |
required | Boolean | false | Adds the 'required' attribute to the form control |
form | String | ID of the form that the form control belongs to. Sets the 'form' attribute on the control | |
autofocus | Boolean | false | When set to 'true', attempts to auto-focus the control when it is mounted, or re-activated when in a keep-alive. Does not set the 'autofocus' attribute on the control |
size Settings | String | Set the size of the component's appearance. 'sm', 'md' (default), or 'lg' | |
state | Boolean | null | Controls the validation state appearance of the component. 'true' for valid, 'false' for invalid', or 'null' for no validation state |
value v-model | String or Number | '' | The current value of the textarea. Result will always be a string, except when the 'number' prop is used |
aria-invalid | Boolean or String | false | Sets the 'aria-invalid' attribute with the specified value |
readonly | Boolean | false | Sets the 'readonly' attribute on the form control |
plaintext | Boolean | false | Set the form control as readonly and renders the control to look like plain text (no borders) |
autocomplete | String | Sets the 'autocomplete' attribute value on the form control | |
placeholder | String | Sets the 'placeholder' attribute value on the form control | |
formatter | Function | reference to a function for formatting the textarea | |
lazy-formatter | Boolean | false | When set, the textarea is formatted on blur instead of each keystroke (if there is a formatter specified) |
trim | Boolean | false | When set, trims any leading and trailing white space from the input value. Emulates the Vue '.trim' v-model modifier |
number | Boolean | false | When set attempts to convert the input value to a native number. Emulates the Vue '.number' v-model modifier |
lazy v2.1.0+ | Boolean | false | When set, updates the v-model on 'change'/'blur' events instead of 'input'. Emulates the Vue '.lazy' v-model modifier |
debounce v2.1.0+ | Number or String | 0 | When set to a number of milliseconds greater than zero, will debounce the user input. Has no effect if prop 'lazy' is set |
rows | Number or String | 2 | The minimum number of rows to display. Must be a value greater than 1 |
max-rows | Number or String | The maximum number of rows to show. When provided, the textarea will grow (or shrink) to fit the content up to maximum rows | |
wrap | String | 'soft' | The value to place on the textarea's 'wrap' attribute. Controls how line break are returned |
no-resize | Boolean | false | When set, disabled the browser's resize handle which prevents the user from changing the height of the textarea. Automatically set when in auto height mode |
no-auto-shrink | Boolean | false | When set, prevents the auto height textarea from shrinking to fit the content |
v-model
Property | Event |
---|---|
value | update |
Event | Arguments | Description |
---|---|---|
input |
| Input event triggered by user interaction. Emitted after any formatting (not including 'trim' or 'number' props) and after the v-model is updated |
change |
| Change event triggered by user interaction. Emitted after any formatting (not including 'trim' or 'number' props) and after the v-model is updated. |
update |
| Emitted to update the v-model |
blur |
| Emitted after the textarea looses focus |
You can import individual components into your project via the following named exports:
Component | Named Export | Import Path |
---|---|---|
<b-form-textarea> | BFormTextarea | bootstrap-vue |
Example:
import { BFormTextarea } from 'bootstrap-vue' Vue.component('b-form-textarea', BFormTextarea)
This plugin includes all of the above listed individual components. Plugins also include any component aliases.
Named Export | Import Path |
---|---|
FormTextareaPlugin | bootstrap-vue |
Example:
import { FormTextareaPlugin } from 'bootstrap-vue' Vue.use(FormTextareaPlugin)