- 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 Numbers into currencies or Dates 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
to be stored in the Redux store. Common use cases are to parse currencies into
Numbers into currencies or localized date formats into Dates.
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.
validate can be a function, an array of functions or an object. In the
latest case, a property of the object is an element of names array. See the
Usage section below for details.
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.
warn can be a function, an array of functions or an object. In the
latest case, a property of the object is an element of names array. See the
Usage section below for details.
forwardRef : 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 are 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.
Passing an object in validate and warn props #
The validate and warn props accepts an object: keys of the objects are elements of the names prop, entries of the object are validate and warn functions.
<Fields
names={['foo', 'bar']}
component={input}
validate={{
foo: (value, allValues, props, name) => 'error'
}}
warn={{
foo: (value, allValues, props) => 'warning'
}}
/>
Instance API #
The following properties and methods are available on an instance of a Field
component.
dirty : boolean #
trueif the current value of any of the fields is different from the initialized value,falseotherwise.
names : Array<String> #
When nested in
FormSection, returns thenamesprop prefixed with theFormSectionname. Otherwise, returns a copy of thenamesprop that you passed in.
pristine : boolean #
trueif the all of the current values are the same as the initialized values,falseotherwise.
values : any #
The current values of the fields. If they are nested, the values will duplicate the structure. For example, if your
namesare[ 'name.first', 'name.last', 'email' ], thevalueswill 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
forwardRefprop, 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...
<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:
{
name: { input: { ... }, meta: { ... } },
email: { input: { ... }, meta: { ... } },
address: {
street: { input: { ... }, meta: { ... } },
city: { input: { ... }, meta: { ... } },
postalCode: { input: { ... }, meta: { ... } }
},
anotherCustomProp: 'Some other information'
}