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In functional components, the ________ hook can be used to mimic the behavior of componentDidMount.

  • useComponentDidMount
  • useEffect
  • useLifecycle
  • useRenderEffect
In functional components, you can use the useEffect hook to mimic the behavior of componentDidMount. The useEffect hook allows you to perform side effects in your components, such as fetching data or setting up subscriptions, after the component has rendered. It's a crucial hook for managing the lifecycle of functional components in React.
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If you want to navigate between different screens in a React Native application, which library/package is commonly used?

  • React Native Navigation
  • React Native Router
  • React Navigation
  • React Router Native
In the context of React Native, the commonly used library for navigating between different screens in an application is "React Navigation." React Navigation provides a comprehensive navigation solution for React Native apps, offering features like stack navigation, tab navigation, and drawer navigation, making it a popular choice among developers for handling navigation within their apps.
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How can you achieve the behavior of componentDidUpdate in functional components?

  • Functional components cannot achieve this behavior.
  • Use the componentDidMount hook.
  • Use the useEffect hook with dependency array.
  • Use the useEffect hook without a dependency array.
You can achieve the behavior of componentDidUpdate in functional components by using the useEffect hook with a dependency array. This allows you to perform side effects after the component has rendered and when specific dependencies change. It is the functional equivalent of componentDidUpdate in class components and is used for handling updates and side effects.
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In your React application, you want to prevent users who are not logged in from accessing certain routes. How would you implement this using React Router?

  • Use the PrivateRoute pattern
  • Use React.auth middleware
  • Use a beforeEnter guard function
  • Use React.AccessControl component
To restrict access to certain routes for non-logged-in users in a React application, you would typically implement the PrivateRoute pattern. This involves creating a custom route component that checks the user's authentication status and redirects them if necessary. The other options are not standard practices for implementing route-based access control.
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Libraries like Immer help in managing state by allowing developers to work with a ________ version of the state.

  • Dynamic
  • Immutable
  • Mutable
  • Static
Libraries like Immer enable developers to work with an "Immutable" version of the state. Immutability ensures that the state cannot be changed after it is created, making it easier to track changes and manage state in complex applications. This is a fundamental concept in state management in Redux and many other libraries.
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Which lifecycle method in class components is considered unsafe and should be avoided in newer versions of React?

  • componentDidMount
  • componentWillMount
  • componentWillReceiveProps
  • componentWillUpdate
The componentWillMount lifecycle method is considered unsafe and should be avoided in newer versions of React. This method may lead to unexpected behavior because it can be called multiple times, potentially causing side effects. In modern React, you should use componentDidMount for similar purposes, as it is more reliable and predictable.
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Which type of component in React allows you to use the render method directly?

  • Class Component
  • Functional Component
  • Pure Component
  • Stateless Component
In React, a Class Component allows you to use the render method directly. Class Components have a render method that returns the JSX to be rendered on the screen. Functional Components, on the other hand, are stateless and don't have a render method in the same way Class Components do.
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You're building a React component that should accept props of different shapes based on a type prop. Which TypeScript feature would be most appropriate to handle this?

  • Conditional Types
  • Intersection Types
  • Type Assertions
  • Union Types
When dealing with React components that accept different props based on a type prop, Union Types are typically the most appropriate TypeScript feature. Union Types allow you to define a prop type that can accept multiple different shapes, providing flexibility in prop definitions based on the type prop value. Conditional Types, Intersection Types, and Type Assertions serve different purposes and are not as suitable for this scenario.
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Your React application uses Apollo Client to fetch data from a GraphQL server. Users have reported seeing outdated data. Which Apollo Client method can you use to forcefully refetch data and bypass the cached results?

  • client.clearCache()
  • client.forceFetch()
  • client.invalidateQuery()
  • client.refetchQuery()
To forcefully refetch data from a GraphQL server and bypass the cached results in Apollo Client, you should use 'client.forceFetch()'. This method makes a fresh request to the server, ensuring that you get the latest data, even if it's already in the cache. 'client.refetchQuery()' is not a standard Apollo Client method, and 'client.invalidateQuery()' and 'client.clearCache()' have different purposes.
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What is the main advantage of using React Fragments over wrapping multiple elements in a div?

  • Fragments allow for conditional rendering.
  • Fragments automatically add unique keys to child elements.
  • Fragments improve rendering performance.
  • Fragments provide more styling options.
The main advantage of using React Fragments over wrapping multiple elements in a div is improved rendering performance. Fragments don't add extra nodes to the DOM, which can lead to better performance, especially when dealing with a large number of elements. They don't introduce extra nesting levels, making it an ideal choice for cleaner, more efficient rendering.
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