React Questions

To ensure data integrity and prevent invalid submissions.

To send data to the server for validation.

To style form elements based on user input.

To automatically submit the form when all fields are filled.

To enforce the data type of props

To style components

To manage component state

To handle user events

{ expression }

{{ expression }}

( expression )

expression

Using refs

Using events

Using state

Using props

It specifies a list of dependencies that trigger the effect when they change.

It defines the effect to be executed.

It provides access to the previous state and props.

It indicates the effect should be executed only once, like componentDidMount.

There is no difference; both are interchangeable.

Functional components are used for complex UI, while class components are used for simple UI.

Functional components are written in JavaScript, while class components are written in JSX.

Class components can have state and lifecycle methods, while functional components cannot.

Enhanced control over form data and validation.

Seamless integration with external libraries for form handling.

Direct manipulation of the DOM for improved performance.

Simplified state management with reduced boilerplate code.

To detach the event handler after it has been executed once

To prevent the default behavior of the event (like form submission)

To stop the event from bubbling up the component tree

To cancel the event entirely and prevent any further actions

To prevent default browser behavior for all events

To ensure that this refers to the correct component instance inside event handlers

To allow passing custom arguments to event handlers

Event binding is not necessary in React; it's an older JavaScript concept.

By wrapping the useEffect call in a conditional statement

By passing an empty array [] as the second argument to useEffect

By not passing a dependency array

By using componentDidMount instead