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Qu'est-ce qu'un composant contrôlé

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2024-08-15 15:54:26850parcourir

Controlled components in React are input elements whose value is managed by React's state. This provides greater control over input values, enabling more complex interactions and enhanced form validation compared to uncontrolled components, where use

Qu'est-ce qu'un composant contrôlé

What is a Controlled Component and How Does it Differ from an Uncontrolled Component?

A controlled component is an input form element whose value is managed and controlled by React's state. Unlike uncontrolled components, which allow users to edit the value directly, controlled components only update their value when the state changes. This gives React complete control over the input's value, allowing for more complex interactions and form validation.

How Do I Create a Controlled Component Using React's Controlled Component API?

To create a controlled component, you typically use the following steps:

  1. Define a state variable to store the input's value.
  2. Use value and onChange props to bind the input to the state.
  3. Update the state whenever the input changes, typically within the onChange handler.

Here's an example:

<code>const [value, setValue] = useState('');

<input type="text" value={value} onChange={e => setValue(e.target.value)} /></code>

What are the Advantages of Using Controlled Components Over Uncontrolled Components?

There are several advantages to using controlled components over uncontrolled components:

  • Improved Form Validation: Controlled components allow for more robust form validation as you can set and check the input's value in the state.
  • State Management: React manages the input's value, ensuring consistency and making it easier to track changes.
  • Complex Interactions: Controlled components are ideal for more complex interactions, such as conditional rendering or updating other state based on input changes.
  • Stateless Components: You can use stateless functional components with controlled components, simplifying code organization.

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