Your application has deeply nested components, and you want to avoid prop drilling. Which React feature would you use to pass user authentication status to all these nested components?
- Context API
- Higher-Order Components (HOCs)
- React Hooks (useState, useContext)
- Redux
To avoid prop drilling in deeply nested components, you can use the Context API. Context allows you to share data, like user authentication status, across components without the need to pass it explicitly through props. While Higher-Order Components (HOCs), Redux, and React Hooks are useful in various scenarios, Context API is specifically designed for this purpose, making it the most suitable choice for passing data down to deeply nested components.
When using the useState hook, the first value in the returned array represents the current state, while the second value is a ________ function to update the state.
- getNewState
- setStateUpdater()
- updateState()
- setStateFunction()
When using the useState hook in React, the first value in the returned array represents the current state, and the second value is a setStateFunction() (or updater function) that allows you to update the state. The updater function accepts the new state or a function that calculates the new state based on the previous state. The other options are not accurate descriptions of the useState hook behavior.
In the context of React's lazy loading, what type of components can be directly imported using React.lazy()?
- Class Components
- Functional Components
- Higher-Order Components
- Redux Components
In the context of React's lazy loading, you can directly import Functional Components using React.lazy(). Class Components and Higher-Order Components are not directly supported for lazy loading using React.lazy(). Redux Components also need to be wrapped in Functional Components to use React.lazy().
How can you make a class property observable in MobX without using decorators?
- Using the @observable decorator.
- By manually wrapping the property in observable().
- It's not possible to make a property observable without decorators in MobX.
- By using Redux instead of MobX.
In MobX, you can make a class property observable without using decorators by manually wrapping the property in the observable() function. This allows you to achieve observability without relying on decorators. The other options are incorrect; using the @observable decorator is a decorator-based approach, and using Redux is a different state management library.
How would you provide multiple contexts to a single component?
- You can achieve this only with Redux.
- You can nest multiple
components. - You can use a higher-order component (HOC) for this purpose.
- You can't provide multiple contexts to a single component.
To provide multiple contexts to a single component in React, you can nest multiple components within your component's structure. Each provider will manage its own context, allowing you to access and update multiple pieces of state within a single component.
When you need direct access to native APIs in React Native, you can write ________ modules.
- Native Access
- Bridge
- JavaScript-to-Native
- Native Interface
When you need direct access to native APIs in React Native, you can write "Native Interface" modules. These modules enable communication between JavaScript code and native code, allowing developers to utilize native APIs seamlessly. The other options do not correctly describe the modules used for this purpose in React Native development.
In the context of React, what would be a potential drawback of overusing Web Workers?
- Improved application performance.
- Increased application responsiveness.
- Complex code and potential bottlenecks in communication with Web Workers.
- Simplified debugging and testing.
Overusing Web Workers in a React application can lead to complex code and potential bottlenecks in communication with Web Workers. While Web Workers can improve performance and responsiveness by offloading heavy tasks, excessive use can introduce complexities in managing multiple threads and their interactions, which may hinder development and debugging efforts. The other options describe potential benefits of using Web Workers but do not address the drawbacks.
Which hook should you use if you need to manage the context within your React application?
- useContext
- useState
- useEffect
- useRef
If you need to manage the context within your React application, you should use the useContext hook. This hook allows you to access and consume data from a context provider. The other options, useState, useEffect, and useRef, are used for managing state, side effects, and references, respectively, but not specifically for managing context.
To ensure a prop has a default value in TypeScript with React, you can use the ________ keyword.
- default
- defaultValue
- optional
- required
To ensure a prop has a default value in TypeScript with React, you can use the defaultValue keyword. This keyword allows you to specify a default value for a prop in case it is not provided when the component is used. It helps in ensuring that the prop always has a value, even if it's not explicitly passed. The other options (default, optional, required) are not standard keywords for specifying default prop values in TypeScript with React.
In the context of React development, how does a Service Worker contribute to the performance and reliability of a web application?
- By optimizing component rendering.
- By enhancing server-side rendering.
- By enabling offline functionality and caching.
- By improving CSS stylesheet management.
In React development, a Service Worker contributes to the performance and reliability of a web application by enabling offline functionality and caching. Service Workers allow web apps to work offline by caching assets and data, providing a seamless experience even when there's no internet connection. This enhances reliability and improves performance. While the other options can be important, they do not directly relate to the role of a Service Worker.