Controlled Components in React
Explore how controlled components in React create predictable and maintainable forms by managing input values through component state. This lesson covers key concepts including two-way data binding with onChange handlers, state synchronization, and practical examples for real-time input handling, character counting, and resettable fields. You'll gain essential skills for building scalable, interactive form interfaces using React's declarative approach.
When building interactive applications, forms are essential for capturing user data. However, relying on direct DOM manipulation to manage inputs often leads to unpredictable results and scattered logic. React introduces a more reliable pattern called controlled components — where every input field’s value is derived from the component’s state. This approach makes form data predictable, easier to debug, and fully aligned with React’s declarative model.
In a controlled form, React takes full control of the input’s value. The input element reflects state, and every change updates that state through event handlers. This two-way synchronization ensures that the UI always mirrors the underlying data, creating a single, consistent source of truth.
Understanding controlled components
A controlled component is a form input element — such as an <input>, <textarea>, or <select> — whose value is controlled by React state. ...