When a change is made to an immutable data structure, it creates a new version without altering the original. This principle is known as ________.
- Alterability
- Changeability
- Immutability
- Mutation
When a change is made to an immutable data structure, it creates a new version without altering the original data. This principle is known as "Immutability." Immutable data structures are essential in functional programming to ensure predictable and safe data manipulation.
How does React handle events differently from plain JavaScript, especially considering browser compatibility issues?
- React directly binds events to DOM elements.
- React relies on browser-specific event APIs.
- React uses a virtual DOM for event handling.
- React uses event delegation for all events.
React handles events differently by using a virtual DOM. It creates event listeners at the root level and uses a synthetic event system to manage event handling. This approach abstracts browser-specific issues and ensures consistent behavior across browsers. It does not directly bind events to DOM elements as in plain JavaScript. This difference is crucial for managing cross-browser compatibility.
For fetching data before rendering a component in a route, you might use the React Router's ________ method.
- fetchComponent
- fetchRoute
- preload
- useEffect
To fetch data before rendering a component in a route with React Router, you can use the preload method. This method allows you to load data asynchronously and ensure it's available before rendering the component associated with the route. Using preload helps improve user experience by reducing unnecessary delays.
React Router provides a hook called ________ that lets you access the state of the current route.
- getCurrentRoute
- getRouteState
- useLocation
- useRouteState
React Router provides a hook called useLocation that allows you to access the state of the current route. This is commonly used to extract parameters or query strings from the URL to determine the current route's state or perform conditional rendering based on the route.
Immutability in state handling can help in avoiding unintended ________ that can arise from direct mutations.
- Bugs
- Optimization issues
- Security breaches
- Side effects
Immutability in state handling primarily helps avoid unintended side effects that can result from direct mutations. When states are immutable, it's easier to reason about the behavior of the program and prevents unintended consequences. It's not primarily about avoiding bugs, optimization issues, or security breaches, although these can be related to proper state management.
What is a Progressive Web App (PWA)?
- A native mobile application.
- A type of server architecture.
- A web application with advanced features.
- A website that cannot be accessed offline.
A Progressive Web App (PWA) is a web application with advanced features that provide a native app-like experience to users. PWAs are designed to be fast, reliable, and work offline. They can be installed on a user's device and have features like push notifications. They are not native mobile apps but offer similar capabilities, making them an excellent choice for web development.
What is the advantage of using immutable data structures in a React application?
- Improved performance due to mutable data.
- Simplicity in managing and tracking data changes.
- Enhanced support for two-way data binding.
- Better compatibility with third-party libraries.
Using immutable data structures in a React application simplifies managing and tracking data changes. When data is immutable, changes create new data objects rather than modifying existing ones, making it easier to understand how and when data changes occur. This leads to more predictable and manageable React applications. The other options do not accurately describe the advantages of immutability in React.
For type-safe operations in React components, props, and state, developers can utilize ________ to add static typing.
- ES6
- Flow
- JavaScript
- TypeScript
Developers can use "TypeScript" to add static typing to React components, props, and state. TypeScript is a statically typed superset of JavaScript, which helps catch type-related errors at compile time, making React code more robust and maintainable.
Which React feature works in tandem with React.lazy to display fallback UI while a component is being lazily loaded?
- React.Suspense
- React.Fallback
- React.LazyUI
- React.Loading
React.Suspense is the React feature that works with React.lazy to display a fallback UI while a component is being lazily loaded. This helps improve the user experience by showing a loading indicator or a fallback UI while the required component is fetched and rendered lazily. Other options like React.Fallback, React.LazyUI, and React.Loading are not standard React features.
When considering Server-Side Rendering (SSR) in React, which framework is widely recognized for this purpose?
- Angular Universal
- Gatsby.js
- Next.js
- Vue Server Renderer
Next.js is widely recognized for Server-Side Rendering (SSR) in React applications. It provides an out-of-the-box solution for SSR, making it easier to implement server-side rendering in React applications. While other frameworks like Angular Universal and Gatsby.js also support SSR, Next.js is particularly popular in the React ecosystem for this purpose.