Creating controlled components for form input in ReactJS

When building forms in ReactJS, it is best practice to create controlled components for handling form inputs. Controlled components are ReactJS components whose value is controlled by ReactJS instead of the DOM. This means that ReactJS manages and updates the value of the form input instead of relying solely on the browser's native behavior.

So why should we use controlled components? Controlled components provide a more robust way to handle form inputs and make it easier to track and manipulate the form's state. When the state of the form changes, ReactJS automatically updates the input value, making it easier to implement features like validation, error handling, and input synchronization.

To create a controlled component for a form input, you need to follow a few simple steps:

Step 1: Set up the component and state First, you need to set up your component and its initial state. Create a class-based component or functional component, and define the initial state using ReactJS's useState hook or this.state.

import React, { useState } from "react";

...

function MyForm() {
  const [inputValue, setInputValue] = useState("");

  ...

  return (
    <form>
      <input
        type="text"
        value={inputValue}
        onChange={(e) => setInputValue(e.target.value)}
      />
      ...
    </form>
  );
}

export default MyForm;

Step 2: Bind the input value to the state Next, you need to bind the value attribute of your input element to the corresponding state variable. In this example, we use the inputValue state variable in the value attribute. We also add an onChange event handler to update the state whenever the input value changes.

Step 3: Handle form submission To handle the form submission, you can add an onSubmit event handler to the form element. In this event handler, you can access the current form state and perform any necessary actions, such as making an API request or updating the database.

...

function MyForm() {
  const [inputValue, setInputValue] = useState("");
  
  const handleSubmit = (e) => {
    e.preventDefault();
    // Do something with the submitted form data
    console.log(inputValue);
  };

  return (
    <form onSubmit={handleSubmit}>
      <input
        type="text"
        value={inputValue}
        onChange={(e) => setInputValue(e.target.value)}
      />
      <button type="submit">Submit</button>
    </form>
  );
}

...

By following these steps, you have successfully created a controlled component for form input in ReactJS. Remember to always use controlled components in your ReactJS forms to have better control over the form's state and provide a more intuitive user experience.

Controlled components not only simplify form handling but also open up possibilities for handling complex form interactions and validations. So next time you are building a form in ReactJS, give controlled components a try and see how they can enhance your form-building experience.