Understanding Forms in React JS: Concepts and Examples

Forms are a crucial component in any web application, allowing users to interact with your site by submitting data or making changes to their profile. In React JS, forms are an essential part of building user-friendly interfaces. In this article, we will discuss the basic concept of forms in React along with its examples and code implementation.

What is a Form in React?

A form in React is a reusable component that allows users to input data. It can be used for various purposes such as submitting data, updating profiles, or making payments. A form typically consists of multiple fields, each representing a specific piece of information, such as text inputs, checkboxes, radio buttons, and more.

Types of Forms in React

There are two main types of forms in React: controlled and uncontrolled forms.

Controlled Form

A controlled form is a type of form where the React component is responsible for rendering the form and also controlling its behavior on subsequent inputs. This means that whenever values inform changes, the component saves the changed value to its state. Here's an example of a controlled input:

```jsx

import React, { useState } from 'react';

function ControlledInput() {

const 'inputValue, setInputValue' = useState('');

return (

First Name:

setInputValue(e.target.value)} />

);

}

```

Uncontrolled Form

An uncontrolled form, on the other hand, is a type of form where the React component does not control its behavior. Instead, the form is controlled by the user's input.

Example of a Controlled Form in React

Let's create an example of a controlled form that allows users to enter their first name and last name. We will use two text fields for this purpose.

```jsx

import React, { useState } from 'react';

function ControlledForm() {

const 'firstName, setFirstName' = useState('');

const 'lastName, setLastName' = useState('');

return (

First Name:

setFirstName(e.target.value)} />

Last Name:

setLastName(e.target.value)} />

);

}

```

In this article, we discussed the basic concept of forms in React and its two types: controlled and uncontrolled forms. We also provided examples and code implementation for a controlled form. Forms are an essential part of building user-friendly interfaces in React, and understanding their concepts and types is crucial for creating effective applications.

Code Implementation

Here's the complete code implementation for the above examples:

```jsx

import React, { useState } from 'react';

function ControlledInput() {

const 'inputValue, setInputValue' = useState('');

return (

First Name:

setInputValue(e.target.value)} />

);

}

function ControlledForm() {

const 'firstName, setFirstName' = useState('');

const 'lastName, setLastName' = useState('');

return (

First Name:

setFirstName(e.target.value)} />

Last Name:

setLastName(e.target.value)} />

);

}

ReactDOM.render(

document.getElementById('root')

);

```

Examples of react js