- Redux Form
- API
Field
Field
#
The Field
component is how you connect each individual input to the Redux store. There are
three fundamental things that you need to understand in order to use Field
correctly:
The
name
prop is required. It is a string path, in dot-and-bracket notation, corresponding to a value in the form values. It may be as simple as'firstName'
or as complicated as'contact.billing.address[2].phones[1].areaCode'
.The
component
prop is required. It may be aComponent
, a stateless function, or a string name of one of the default supported DOM inputs (input
,textarea
orselect
) (see the Usage section below). To learn about the props that will be provided to whatever yourcomponent
is, see the Props section below.All other props will be passed along to the element generated by the
component
prop.
Importing #
var Field = require('redux-form').Field; // ES5
import { Field } from 'redux-form'; // ES6
Props you can pass to Field
#
name : String
[required] #
A string path, in dot-and-bracket notation, corresponding to a value in the form values. It may
be as simple as 'firstName'
or as complicated as
contact.billing.address[2].phones[1].areaCode
. See the Usage section below for details.
Numeric field names, e.g. name="42"
or name="foo.5.email"
, are not supported, as they can
be confused for array indexes.
component : Component|Function|String
[required] #
A Component
, stateless function, or string corresponding to a default JSX element.
See the Usage section below for details.
format : (value, name) => formattedValue
[optional] #
Formats the value from the Redux store to be displayed in the field input. Common use cases are
to format Number
s into currencies or Date
s into a localized date format.
format
is called with the field value
and name
as arguments and should return the
new formatted value to be displayed in the field input.
To respect React 15 input behavior there is defaultFormat = value => value == null ? '' : value
internally used. To disable that you can pass null
as format
prop.
normalize : (value, previousValue, allValues, previousAllValues) => nextValue
[optional] #
A function to convert whatever value the user has entered into the value that you want stored in
the Redux store for the field. For instance, if you want the value to be in all uppercase, you
would pass value => value.toUpperCase()
. The parameters to your normalize function are:
value : any
#The value entered by the user.
previousValue : any
#The previous value for the field.
allValues : Object
#All the values in the entire form with the new value. This will be an Immutable
Map
if you are using Immutable JS.
previousAllValues : Object
#All the values in the entire form before the current change. This will be an Immutable
Map
if you are using Immutable JS.
onBlur : (event, newValue, previousValue) => void
[optional] #
A callback that will be called whenever an onBlur
event is fired from the underlying input.
If you call event.preventDefault()
, the BLUR
action will NOT be dispatched, and the value
and focus state will not be updated in the Redux store.
onChange : (event, newValue, previousValue) => void
[optional] #
A callback that will be called whenever an onChange
event is fired from the underlying input.
If you call event.preventDefault()
, the CHANGE
action will NOT be dispatched, and the value
will not be updated in the Redux store.
onDragStart : (event) => void
[optional] #
A callback that will be called whenever an onDragStart
event is fired from the underlying input.
onDrop : (event, newValue, previousValue) => void
[optional] #
A callback that will be called whenever an onDrop
event is fired from the underlying input.
If you call event.preventDefault()
, the CHANGE
action will NOT be dispatched, and the value
will not be updated in the Redux store.
onFocus : (event) => void
[optional] #
A callback that will be called whenever an onFocus
event is fired from the underlying input.
If you call event.preventDefault()
, the FOCUS
action will NOT be dispatched, and
the focus state will not be updated in the Redux store.
props : object
[optional] #
Object with custom props to pass through the Field
component into a component provided
to component
prop. This props will be merged to props provided by Field
itself. This may be
useful if you are using TypeScript. This construct is completely optional; the primary way of
passing props along to your component
is to give them directly to the Field
component, but
if, for whatever reason, you prefer to bundle them into a separate object, you may do so by
passing them into props
.
parse : (value, name) => parsedValue
[optional] #
Parses the value given from the field input component to the type that you want stored in the
Redux store. Common use cases are to parse currencies into Number
s or
localized date formats into Date
s.
parse
is called with the field value
and name
as arguments and should return the new
parsed value to be stored in the Redux store.
validate : (value, allValues, props, name) => error
[optional] #
Allows you to to provide a field-level validation rule. The function is given the fields current value, all other form values, the props passed to the form, and the name of field currently being validated. If the field is valid it should return undefined
. If the field is invalid it should return an error (usually, but not necessarily, a String
). Note: if the validate prop changes the field will be re-registered.
warn : (value, allValues, props) => warning
[optional] #
Allows you to to provide a field-level warning rule. The function is given the fields current value, all other form values, and the props passed to the form. If the field does not need a warning it should return undefined
. If the field needs a warning it should return the warning (usually, but not necessarily, a String
). Note: if the warn prop changes the field will be re-registered.
withRef : boolean
[optional] #
If true
, the rendered component will be available with the getRenderedComponent()
method.
Defaults to false
. Cannot be used if your component is a stateless function component.
Usage #
The component
prop will be passed to
React.createElement()
,
which accepts one of three possible things:
1. A component #
This can be any component class that you have written or have imported from a third party library.
// MyCustomInput.js
import React, { Component } from 'react'
class MyCustomInput extends Component {
render() {
const { input: { value, onChange } } = this.props
return (
<div>
<span>The current value is {value}.</span>
<button type="button" onClick={() => onChange(value + 1)}>Inc</button>
<button type="button" onClick={() => onChange(value - 1)}>Dec</button>
</div>
)
}
}
Then, somewhere in your form...
import MyCustomInput from './MyCustomInput'
...
<Field name="myField" component={MyCustomInput}/>
To learn what props will be passed to your component, see the Props section below.
2. A stateless function #
This is the most flexible way to use <Field>
, as it gives you complete control over how the
input is rendered. It is especially useful for displaying validation errors. It will also be the
most familiar to people migrating from previous versions of redux-form
. You must define the
stateless function outside of your render()
method, or else it will be recreated on every
render and will force the Field
to rerender because its component
prop will be different.
If you are defining your stateless function inside of render()
, it will not only be slower, but
your input will lose focus whenever the entire form component rerenders.
// outside your render() method
const renderField = (field) => (
<div className="input-row">
<input {...field.input} type="text"/>
{field.meta.touched && field.meta.error &&
<span className="error">{field.meta.error}</span>}
</div>
)
// inside your render() method
<Field name="myField" component={renderField}/>
To learn what props will be passed to your stateless function, see the Props section below.
3. A string: input
, select
, or textarea
#
So all you really need to render an redux-form
-connected text input is:
<Field component="input" type="text"/>
Remember the third rule above that all other props are passed to the element generated by
component
? So the type="text"
prop will be given to the input.
Instance API #
The following properties and methods are available on an instance of a Field
component.
dirty : boolean
#
true
if the current value is different from the initialized value,false
otherwise.
name : String
#
When nested in
FormSection
, returns thename
prop prefixed with theFormSection
name. Otherwise, returns thename
prop that you passed in.
pristine : boolean
#
true
if the current value is the same as the initialized value,false
otherwise.
value : any
#
The current value of the field.
getRenderedComponent()
#
Returns the instance of the rendered component. For this to work, you must provide a
withRef
prop, and your component must not be a stateless function component.
####
Props #
These are props that Field
will pass to your wrapped component. The props provided by redux-form
are divided into input
and meta
objects.
Any custom props passed to Field
will be merged into the props object on the same level as the input
and meta
objects.
Input Props #
The props under the input
key are what connects your input component to Redux and are meant
to be destructured into your <input/>
component.
input.checked : boolean
[optional] #
An alias for
value
only whenvalue
is a boolean. Provided for convenience of destructuring the whole field object into the props of a form element.
input.name : String
#
When nested in
FormSection
, returns thename
prop prefixed with theFormSection
name. Otherwise, returns thename
prop that you passed in.
input.onBlur(eventOrValue) : Function
#
A function to call when the form field loses focus. It expects to either receive the React SyntheticEvent or the current value of the field.
input.onChange(eventOrValue) : Function
#
A function to call when the form field is changed. It expects to either receive the React SyntheticEvent or the new value of the field.
input.onDragStart(event) : Function
#
A function to call when the form field receives a
dragStart
event. Saves the field value in the event for giving the field it is dropped into.
input.onDrop(event) : Function
#
A function to call when the form field receives a
drop
event.
input.onFocus(event) : Function
#
A function to call when the form field receives focus.
input.value: any
#
The value of this form field. It will be a boolean for checkboxes, and a string for all other input types. If there is no value in the Redux state for this field, it will default to
''
. This is to ensure that the input is controlled. If you require that the value be of another type (e.g.Date
orNumber
), you must provideinitialValues
to your form with the desired type of this field.
Meta Props #
The props under the meta
key are metadata about the state of this field that redux-form
is
tracking for you.
meta.active : boolean
#
true
if this field currently has focus. It will only work if you are passingonFocus
to your input element.
meta.autofilled : boolean
#
true
if this field has been set with theAUTOFILL
action and has not since been changed with aCHANGE
action. This is useful to render the field in a way that the user can tell that the value was autofilled for them.
meta.asyncValidating : boolean
#
true
if the form is currently running asynchronous validation because this field was blurred.
meta.dirty : boolean
#
true
if the field value has changed from its initialized value. Opposite ofpristine
.
meta.dispatch : Function
#
The Redux
dispatch
function.
meta.error : String
[optional] #
The error for this field if its value is not passing validation. Both synchronous, asynchronous, and submit validation errors will be reported here.
meta.form : String
#
The name of the
form
. Could be useful if you want to manually dispatch actions.
meta.initial : any
#
The initial value of the field.
meta.invalid : boolean
#
true
if the field value fails validation (has a validation error). Opposite ofvalid
.
meta.pristine : boolean
#
true
if the field value is the same as its initialized value. Opposite ofdirty
.
meta.submitting : boolean
#
true
if the field is currently being submitted
meta.submitFailed : boolean
#
true
if the form hadonSubmit
called and failed to submit for any reason. A subsequent successful submit will set it back to false.
meta.touched : boolean
#
true
if the field has been touched. By default this will be set when the field is blurred.
meta.valid : boolean
#
true
if the field value passes validation (has no validation errors). Opposite ofinvalid
.
meta.visited: boolean
#
true
if this field has ever had focus. It will only work if you are passingonFocus
to your input element.
meta.warning : String
[optional] #
The warning for this field if its value is not passing warning validation.