- Redux Form
- API
Fields
Fields
#
The Fields
component is similar to the
Field
component, but operates on multiple
fields with a single connected component. Rather than passing a single name
prop, Fields
takes an array of names in
the names
prop.
IMPORTANT: Connecting to multiple fields should be used sparingly, as it will require the
entire <Fields>
component to re-render every time any of the fields it is connected to change.
This can be a performance bottleneck. Unless you absolutely need to, you should connect to your
fields individually with <Field>
.
Importing #
var Fields = require('redux-form').Fields; // ES5
import { Fields } from 'redux-form'; // ES6
Props you can pass to Fields
#
names : Array<String>
[required] #
An array of strings (or the pseudo-array fields
provided by
FieldArray
),
in dot-and-bracket notation, corresponding to form values. They may
be as simple as 'firstName'
or as complicated as
contact.billing.address[2].phones[1].areaCode
. See the Usage section below for details.
component : Component|Function
[required] #
A Component
or stateless function that will be given all the props necessary to render the
field inputs. 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.
props : object
[optional] #
Object with custom props to pass through the Fields
component into a component provided
to component
prop. This props will be merged to props provided by Fields
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 Fields
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 into currencies 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.
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 two possible things:
1. A component #
This can be any component class that you have written or have imported from a third party library.
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 <Fields>
, as it gives you complete control over how the
inputs 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 Fields
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 renderFields = (fields) => (
<div>
<div className="input-row">
<input {...fields.firstName.input} type="text"/>
{fields.firstName.meta.touched && fields.firstName.meta.error &&
<span className="error">{fields.firstName.meta.error}</span>}
</div>
<div className="input-row">
<input {...fields.lastName.input} type="text"/>
{fields.lastName.meta.touched && fields.lastName.meta.error &&
<span className="error">{fields.lastName.meta.error}</span>}
</div>
</div>
)
// inside your render() method
<Fields names={[ 'firstName', 'lastName' ]} component={renderFields}/>
To learn what props will be passed to your stateless function, see the Props section below.
Instance API #
The following properties and methods are available on an instance of a Field
component.
dirty : boolean
#
true
if the current value of any of the fields is different from the initialized value,false
otherwise.
names : Array<String>
#
When nested in
FormSection
, returns thenames
prop prefixed with theFormSection
name. Otherwise, returns a copy of thenames
prop that you passed in.
pristine : boolean
#
true
if the all of the current values are the same as the initialized values,false
otherwise.
values : any
#
The current values of the fields. If they are nested, the values will duplicate the structure. For example, if your
names
are[ 'name.first', 'name.last', 'email' ]
, thevalues
will be{ name: { first: 'John', last: 'Smith' }, email: '[email protected]' }
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 #
The props that Fields
will pass to your component are the same input
and meta
structures
that Field
generates, except that
they are broken up into the structure of the fields you gave as names
.
Any additional props that you pass to Field
will be included at the root of the props structure
given to your component
For example, if the fields you gave are...
x
<Fields
names={[
'name',
'email',
'address.street',
'address.city',
'address.postalCode'
]}
component={MyMultiFieldComponent}
anotherCustomProp="Some other information"/>
...the props given to your component would be of the structure:
x
{
name: { input: { ... }, meta: { ... } },
email: { input: { ... }, meta: { ... } },
address: {
street: { input: { ... }, meta: { ... } },
city: { input: { ... }, meta: { ... } },
postalCode: { input: { ... }, meta: { ... } }
},
anotherCustomProp: 'Some other information'
}