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, formState: { 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 defaultValue="test" {...register("example")} />
{/* include validation with required or other standard HTML validation rules */}
<input {...register("exampleRequired", { required: true })} />
{/* errors will return when field validation fails */}
{errors.exampleRequired && <span>This field is required</span>}
<input type="submit" />
</form>
);
}
♦
React Web 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 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 name
as a key for the registration process.
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 {...register("firstName")} />
<select {...register("gender")}>
<option value="female">female</option>
<option value="male">male</option>
<option value="other">other</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 {...register("firstName", { required: true, maxLength: 20 })} />
<input {...register("lastName", { pattern: /^[A-Za-z]+$/i })} />
<input type="number" {...register("age", { min: 18, max: 99 })} />
<input type="submit" />
</form>
);
}
Integrating an existing form
Integrating an existing form should be simple. The important step is to register
the component's ref
and assign relevant props to your input.
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 {...register(label, { required })} />
</>
);
// you can use React.forwardRef to pass the ref too
const Select = React.forwardRef(({ onChange, onBlur, name, label }, ref) => (
<>
<label>{label}</label>
<select name={name} ref={ref} onChange={onChange} onBlur={onBlur}>
<option value="20">20</option>
<option value="30">30</option>
</select>
</>
));
export default function App() {
const { register, handleSubmit } = useForm();
const onSubmit = (data) => {
alert(JSON.stringify(data));
};
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Input label="First Name" register={register} required />
<Select label="Age" {...register("Age")} />
<input type="submit" />
</form>
);
};
Integrating with UI libraries
React Hook Form has made it easy to integrate with external UI component libraries. If the component doesn't expose input's ref
, then you should use the Controller component, which will take care of the registration process.
import React from "react";
import Select from "react-select";
import { useForm, Controller } from "react-hook-form";
import Input from "@material-ui/core/Input";
export default function App() {
const { control, handleSubmit } = useForm({
defaultValues: {
firstName: '',
select: {}
}
});
const onSubmit = data => console.log(data);
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Controller
name="firstName"
control={control}
render={({ field }) => <Input {...field} />}
/>
<Controller
name="select"
control={control}
render={({ field }) => <Select
{...field}
options={[
{ value: "chocolate", label: "Chocolate" },
{ value: "strawberry", label: "Strawberry" },
{ value: "vanilla", label: "Vanilla" }
]}
/>}
/>
<input type="submit" />
</form>
);
};
Integrating Controlled Inputs
This library embraces uncontrolled components and native HTML inputs, however, it's hard to avoid working with external controlled components such as React-Select, AntD and Material-UI. To make this simple, we provide a wrapper component: Controller to streamline the integration process while still giving you the freedom to use a custom register.
import React from "react";
import { useForm, Controller } from "react-hook-form";
import { TextField, Checkbox } from "@material-ui/core";
function App() {
const { handleSubmit, control, reset } = useForm({
defaultValues: {
checkbox: false,
}
});
const onSubmit = data => console.log(data);
return (
<form onSubmit={handleSubmit(onSubmit)}>
<Controller
name="checkbox"
control={control}
rules={{ required: true }}
render={({ field }) => <Checkbox {...field} />}
/>
<input type="submit" />
</form>
);
}
Integrating with global state
It doesn't require you to rely on a state management library, but you can easily integrate with them.
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 {...register("firstName")} defaultValue={props.firstName} />
<Input {...register("lastName")} defaultValue={props.lastName} />
<input type="submit" />
</form>
);
}
// Connect your component with redux
connect(({ firstName, lastName }) => ({ firstName, lastName }), updateAction)(YourForm);
Handle errors
React Hook Form provides an errors
object to show you the errors in the form. errors
's type will return given validation constraints. The following example showcases a required validation rule.
import React from "react";
import { useForm } from "react-hook-form";
const onSubmit = data => console.log(data);
export default function App() {
const { register, formState: { errors }, handleSubmit } = useForm();
return (
<form onSubmit={handleSubmit(onSubmit)}>
<input {...register("firstName", { required: true })} />
{errors.firstName?.type === 'required' && "First name is required"}
<input {...register("lastName", { required: true })} />
{errors.lastName && "Last name is required"}
<input type="submit" />
</form>
);
}
Schema Validation
We also support schema-based form validation with Yup, Zod , Superstruct & Joi, where you can pass your schema
to useForm as an optional config. It will validate your input data against the schema and return with either errors or a valid result.
Step 1: Install Yup
into your project.
Step 2: Prepare your schema for validation and register inputs with React Hook Form.
import React from "react";
import { useForm } from "react-hook-form";
import { yupResolver } from '@hookform/resolvers/yup';
import * as yup from "yup";
const schema = yup.object({
firstName: yup.string().required(),
age: yup.number().positive().integer().required(),
}).required();
export default function App() {
const { register, handleSubmit, formState:{ errors } } = useForm({
resolver: yupResolver(schema)
});
const onSubmit = data => console.log(data);
return (
<form onSubmit={handleSubmit(onSubmit)}>
<input {...register("firstName")} />
<p>{errors.firstName?.message}</p>
<input {...register("age")} />
<p>{errors.age?.message}</p>
<input type="submit" />
</form>
);
}
React Native
You will get the same performance boost and enhancement in React Native. To integrate with input component, you can wrap it with Controller
.
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, formState: { errors } } = useForm({
defaultValues: {
firstName: '',
lastName: ''
}
});
const onSubmit = data => console.log(data);
return (
<View>
<Controller
control={control}
rules={{
required: true,
}}
render={({ field: { onChange, onBlur, value } }) => (
<TextInput
style={styles.input}
onBlur={onBlur}
onChangeText={onChange}
value={value}
/>
)}
name="firstName"
/>
{errors.firstName && <Text>This is required.</Text>}
<Controller
control={control}
rules={{
maxLength: 100,
}}
render={({ field: { onChange, onBlur, value } }) => (
<TextInput
style={styles.input}
onBlur={onBlur}
onChangeText={onChange}
value={value}
/>
)}
name="lastName"
/>
<Button title="Submit" onPress={handleSubmit(onSubmit)} />
</View>
);
}
TypeScript
React Hook Form is built with TypeScript
, and 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, formState: { errors } } = useForm<FormData>();
const onSubmit = handleSubmit(data => console.log(data));
// firstName and lastName will have correct type
return (
<form onSubmit={onSubmit}>
<label>First Name</label>
<input {...register("firstName")} />
<label>Last Name</label>
<input {...register("lastName")} />
<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.