Installation
Installing React Hook Form only takes a single command and you're ready to roll.
npm install react-hook-formExample
The following code excerpt demonstrates a basic usage example:
import React from 'react'
import { useForm } from 'react-hook-form'
export default function App() {
const { register, handleSubmit, watch, errors } = useForm()
const onSubmit = data => { console.log(data) }
console.log(watch('example')) // watch input value by passing the name of it
return (
{/* "handleSubmit" will validate your inputs before invoking "onSubmit" */}
<form onSubmit={handleSubmit(onSubmit)}>
{/* register your input into the hook by invoking the "register" function */}
<input name="example" defaultValue="test" ref={register} />
{/* include validation with required or other standard HTML validation rules */}
<input name="exampleRequired" ref={register({ required: true })} />
{/* errors will return when field validation fails */}
{errors.exampleRequired && <span>This field is required</span>}
<input type="submit" />
</form>
)
}
♦
Video Tutorial
This video tutorial illustrates the basic usage and concepts of React Hook Form.
Register fields
One of the key concepts in React Hook Form is to register
your uncontrolled component into the Hook. This will make its value available for both the form validation and submission.
Note: Each field is required to have a unique name
as a key for the registration process.
Note: React Native will require you to either use a manual register command: register({ name: 'test' }, { required: true })
or a Controller to wrap and register your component automatically. Learn more in the dedicated section for React Native.
import React from 'react'
import { useForm } from 'react-hook-form'
export default function App() {
const { register, handleSubmit } = useForm()
const onSubmit = data => console.log(data)
return (
<form onSubmit={handleSubmit(onSubmit)}>
<input name="firstName" ref={register} />
<select name="gender" ref={register}>
<option value="male">male</option>
<option value="female">female</option>
</select>
<input type="submit" />
</form>
);
}
Apply validation
React Hook Form makes form validation easy by aligning with the existing HTML standard for form validation.
List of validation rules supported:
- required
- min
- max
- minLength
- maxLength
- pattern
- validate
You can read more detail on each rule in the register section.
import React from 'react'
import { useForm } from 'react-hook-form'
export default function App() {
const { register, handleSubmit } = useForm()
const onSubmit = data => console.log(data)
return (
<form onSubmit={handleSubmit(onSubmit)}>
<input name="firstName" ref={register({ required: true, maxLength: 20 })} />
<input name="lastName" ref={register({ pattern: /^[A-Za-z]+$/i })} />
<input name="age" type="number" ref={register({ min: 18, max: 99 })} />
<input type="submit" />
</form>
);
}
Adapting existing form
Working on an existing form is simple. The important step is to applyregister
into existing component's ref
.import React from 'react'
import { useForm } from 'react-hook-form'
// The following component is an example of your existing Input Component
const Input = ({ label, register, required }) => (
<>
<label>{label}</label>
<input name={label} ref={register({ required })} />
</>
)
// you can use React.forwardRef to pass the ref too
const Select = React.forwardRef(({ label, register }, ref) => (
<>
<label>{label}</label>
<select name={label} ref={ref}>
<option value="20">20</option>
<option value="30">30</option>
</select>
</>
))
export default function App() {
const { register, handleSubmit } = useForm()
const onSubmit = data => console.log(data)
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Input label="First Name" ref={register} required />
<Select label="Age" ref={register} />
<input type="submit" />
</form>
)
}
Work with UI library
React Hook Form has made it easy to integrate with external UI component libraries.
Option 1: The best way is to check if the component you wish to use exposes an innerRef
or ref
that can be used to register
. For example: Material-UI's TextField
accepts inputRef
as one of its props. You can simply pass register
to it.
<TextField inputRef={register} label="First name" name="FirstName"/>
Option 2: Sometimes components don't expose a prop to register, for example react-select
or react-datepicker
.
The second easiest way is to use the Controller wrapper component, which will take care of the registration process for you.
import React from "react";
import { useForm, Controller } from "react-hook-form";
import Select from "react-select";
import Input from "@material-ui/core/Input";
import { Input as InputField } from "antd";
export default function App() {
const { control, handleSubmit } = useForm();
const onSubmit = data => console.log(data);
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Controller as={<Input />} name="HelloWorld" control={control} defaultValue="" />
<Controller as={<InputField />} name="AntdInput" control={control} defaultValue="" />
<Controller
as={<Select />}
name="reactSelect"
control={control}
onChange={([selected]) => {
// React Select return object instead of value for selection
return { value: selected };
}}
defaultValue={{}}
/>
<input type="submit" />
</form>
);
}
Option 3: Lastly we can set up a custom register using the useEffect Hook and update the value via setValue
.
import React from 'react';
import { useForm } from 'react-hook-form';
import Select from "react-select";
import Input from "@material-ui/core/Input";
import { Input as InputField } from 'antd';
export default function App() {
const { register, handleSubmit, setValue } = useForm();
const onSubmit = data => console.log(data);
const [values, setReactSelectValue] = useState({ selectedOption: [] });
const handleMultiChange = selectedOption => {
setValue("reactSelect", selectedOption);
setReactSelectValue({ selectedOption });
}
const handleChange = (e) => {
setValue("AntdInput", e.target.value);
}
React.useEffect(() => {
register({ name: "reactSelect" }); // custom register react-select
register({ name: "AntdInput" }); // custom register antd input
}, [register])
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Input name="HelloWorld" inputRef={register} />
<InputField name="AntdInput" onChange={handleChange} />
<Select
value={values.selectedOption}
options={options}
onChange={handleMultiChange}
isMulti
/>
<input type="submit" />
</form>
);
}
Controlled Input
React Hook Form embrace uncontrolled components and native HTML inputs, however it's hard to avoid working with external controlled component such as React-Select, AntD and Material-UI, hence we have built a wrapper component: Controller to streamline the integration process while still giving you the freedom to use custom register with your needs.
Read more about the Controller component.
import React from "react";
import { useForm, Controller } from "react-hook-form";
import ReactSelect from "react-select";
import { TextField, Checkbox } from "@material-ui/core";
function App() {
const methods = useForm();
const { handleSubmit, control, reset } = methods;
const onSubmit = data => console.log(data);
return (
<form onSubmit={handleSubmit(onSubmit)}>
{/* Option 1 (preferred): pass a component to the Controller. */}
<Controller as={TextField} name="TextField" control={control} defaultValue="" />
{/* Option 2: pass a JSX element to the Controller. */}
{/* Note that any prop passed to the element will be overriden. */}
{/* In this case, "SomeName" will be changed to "MyCheckbox". */}
<Controller
as={<Checkbox name="SomeName"/>}
name="MyCheckbox"
value="test"
control={control}
defaultValue={false}
/>
<button>Submit</button>
</form>
);
}
Integrate global state
React Hook Form doesn't require you to rely on a state management library such as Redux to store your data, but you can easily integrate with it:import React from 'react'
import { useForm } from 'react-hook-form'
import { connect } from 'react-redux'
import updateAction from './actions'
export default function App(props) {
const { register, handleSubmit, setValue } = useForm()
// Submit your data into Redux store
const onSubmit = (data) => props.updateAction(data)
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Input name="firstName" defaultValue={props.firstName} ref={register} />
<Input name="lastName" defaultValue={props.lastName} ref={register} />
<input type="submit" />
</form>
);
}
// Connect your component with redux
connect(({ firstName, lastName }) => ({ firstName, lastName }), updateAction)(YourForm)
Handle errors
React Hook Form provides anerrors
object to show you the errors in the form.import React from 'react'
import { useForm } from 'react-hook-form'
export default function App() {
const { register, errors, handleSubmit } = useForm()
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Input name="firstName" ref={register({ required: true })} />
{errors.firstName && 'First name is required'}
<Input name="lastName" ref={register({ required: true })} />
{errors.lastName && 'Last name is required'}
<input type="submit" />
</form>
);
}
React Native
You will get the same performance enhancement from an Uncontrolled Component. However, there are certain APIs which are not compatible with React Native (due to the API differences between web and native). You will have to use a manual register as shown in the following example.
import React from "react";
import { Text, View, TextInput, Button, Alert } from "react-native";
import { useForm, Controller } from "react-hook-form";
export default function App() {
const { control, handleSubmit, errors } = useForm();
const onSubmit = data => Alert.alert("Form Data", data);
const onChange = args => {
return {
value: args[0].nativeEvent.text,
};
};
return (
<View>
<Text>First name</Text>
<Controller
as={<TextInput />}
control={control}
name="firstName"
onChange={onChange}
rules={{ required: true }}
defaultValue=""
/>
{errors.firstName && <Text>This is required.</Text>}
<Text>Last name</Text>
<Controller as={<TextInput />} control={control} name="lastName" defaultValue="" />
<Button onPress={handleSubmit(onSubmit)} />
</View>
);
}
TypeScript
React Hook Form is built with Typescript
, so you can define a FormData
type to support form values.
import * as React from "react";
import { useForm } from "react-hook-form";
type FormData = {
firstName: string;
lastName: string;
};
export default function App() {
const { register, setValue, handleSubmit, errors } = useForm<FormData>();
const onSubmit = handleSubmit(({ firstName, lastName }) => {
console.log(firstName, lastName);
}); // firstName and lastName will have correct type
return (
<form onSubmit={onSubmit}>
<label>First Name</label>
<input name="firstName" ref={register} />
<label>Last Name</label>
<input name="lastName" ref={register} />
<button
type="button"
onClick={() => {
setValue("lastName", "luo"); // ✅
setValue("firstName", true); // ❌: true is not string
errors.bill; // ❌: property bill does not exist
}}
>
SetValue
</button>
</form>
);
}
Want to learn more?
Check out the React Hook Form documentation and learn all about the API.