Controlled vs Uncontrolled React.js components

React.js is a popular JavaScript library for building user interfaces. When working with React components, you may come across the concepts of controlled and uncontrolled components. These terms refer to how the components manage and update their state and data.

Controlled Components

A controlled component is one where the component’s state is controlled by React. This means that the component receives its current value from the parent component and notifies the parent component whenever the value changes. The parent component also manages the component’s behavior and updates its state accordingly.

Controlled components are commonly used for form inputs, such as text fields, checkboxes, and radio buttons. In a controlled input, the value of the input is controlled by React state and is updated through onChange events.

Uncontrolled Components

An uncontrolled component is one where the component manages its own state internally. This means that the component has its own state and updates it internally without involving the parent component. The parent component does not have direct access to the component’s state or data.

Uncontrolled components are useful for building reusable components that manage their own state and behavior. They are also commonly used for integrating with third-party libraries or for managing complex state logic within a component.

Which one to choose?

When deciding whether to use controlled or uncontrolled components, consider the specific requirements of your application and the level of control you need over the component’s state. Controlled components offer more predictable and centralized state management, whereas uncontrolled components offer more flexibility and reusability.

In general, controlled components are recommended for simple forms and inputs, while uncontrolled components are recommended for more complex or custom components. However, the choice between controlled and uncontrolled components ultimately depends on the specific needs and goals of your application.

Overall, both controlled and uncontrolled components have their own advantages and use cases, and the choice between them should be based on the specific requirements and design goals of your application.