React Forms and Events 2

Question 1

Which React hook is typically used to access the value of an uncontrolled form input?

Accepted Answer

useRef

Answer

useRef creates a ref object that can be attached to a DOM element, allowing direct access to the uncontrolled input's current value via ref.current.value.

Question 2

What are React SyntheticEvents?

Accepted Answer

Cross-browser wrappers around native browser events

Answer

React's SyntheticEvent wraps native browser events to provide a consistent, cross-browser API so developers don't need to handle browser differences.

Question 3

How is a controlled `<textarea>` in React different from a standard HTML textarea?

Accepted Answer

React textareas use `value` prop and onChange, not content between tags

Answer

In React, a controlled textarea uses the `value` prop bound to state and an onChange handler, unlike HTML where content goes between opening and closing tags.

Question 4

What is the correct way to control which option is selected in a React `<select>` element?

Accepted Answer

Set the `value` prop on the `<select>` element and update via onChange

Answer

React uses the `value` prop on the `<select>` element to control which option is selected, replacing the HTML approach of using `selected` on individual options.

Question 5

What does `event.stopPropagation()` do in a React event handler?

Accepted Answer

Stops the event from bubbling up to parent elements

Answer

stopPropagation prevents the event from bubbling up through the DOM tree, so parent elements won't also receive and handle the event.

React Practice Test

React Practice Test

React Forms and Events 2