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bookReact Hooks and Context Wrap-Up

useState Hook

  • The useState hook is used to add state functionality;
  • It allows us to declare and manage state variables within a component;
  • By calling the useState hook, we can initialize a state variable and a corresponding setter function;
  • Updating the state variable triggers a re-render of the component, reflecting the new state value.

useRef Hook

  • The useRef hook provides a way to create mutable variables that persist across component renders;
  • Unlike useState, useRef doesn't trigger a re-render when its value changes;
  • It's commonly used to access or store references to DOM elements, manage previous values, or preserve values between renders.

useEffect Hook

  • The useEffect hook enables us to perform side effects;
  • We can use useEffect to handle tasks such as data fetching, subscriptions, or interacting with the DOM;
  • By specifying dependencies, we control when the effect runs, optimizing performance and preventing unnecessary re-renders.

useMemo Hook

  • The useMemo hook allows for the memoization of expensive calculations or computations;
  • It takes a function and a dependencies array and returns a memoized value;
  • Providing a dependencies array ensures that the memoized value is only recomputed when the dependencies change. This optimization can significantly improve performance by avoiding unnecessary recalculations.

Context

  • Context allows passing data through the component tree without requiring explicit props drilling;
  • It enables global state management and allows components to access shared data;
  • Context consists of two main parts: the Context object and the Context Provider;
  • The Context object holds the shared data, while the Provider component wraps the part of the component tree that needs access to that data;
  • Consuming components can access the data using the useContext hook.

1. Which hook is used to access shared data from a Context in a consuming component?

2. When using the useEffect hook, what is the purpose of specifying dependencies in the dependency array?

3. What is the primary benefit of memoizing values using the useMemo hook?

question mark

Which hook is used to access shared data from a Context in a consuming component?

Select the correct answer

question mark

When using the useEffect hook, what is the purpose of specifying dependencies in the dependency array?

Select the correct answer

question mark

What is the primary benefit of memoizing values using the useMemo hook?

Select the correct answer

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 3. ChapterΒ 13

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bookReact Hooks and Context Wrap-Up

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useState Hook

  • The useState hook is used to add state functionality;
  • It allows us to declare and manage state variables within a component;
  • By calling the useState hook, we can initialize a state variable and a corresponding setter function;
  • Updating the state variable triggers a re-render of the component, reflecting the new state value.

useRef Hook

  • The useRef hook provides a way to create mutable variables that persist across component renders;
  • Unlike useState, useRef doesn't trigger a re-render when its value changes;
  • It's commonly used to access or store references to DOM elements, manage previous values, or preserve values between renders.

useEffect Hook

  • The useEffect hook enables us to perform side effects;
  • We can use useEffect to handle tasks such as data fetching, subscriptions, or interacting with the DOM;
  • By specifying dependencies, we control when the effect runs, optimizing performance and preventing unnecessary re-renders.

useMemo Hook

  • The useMemo hook allows for the memoization of expensive calculations or computations;
  • It takes a function and a dependencies array and returns a memoized value;
  • Providing a dependencies array ensures that the memoized value is only recomputed when the dependencies change. This optimization can significantly improve performance by avoiding unnecessary recalculations.

Context

  • Context allows passing data through the component tree without requiring explicit props drilling;
  • It enables global state management and allows components to access shared data;
  • Context consists of two main parts: the Context object and the Context Provider;
  • The Context object holds the shared data, while the Provider component wraps the part of the component tree that needs access to that data;
  • Consuming components can access the data using the useContext hook.

1. Which hook is used to access shared data from a Context in a consuming component?

2. When using the useEffect hook, what is the purpose of specifying dependencies in the dependency array?

3. What is the primary benefit of memoizing values using the useMemo hook?

question mark

Which hook is used to access shared data from a Context in a consuming component?

Select the correct answer

question mark

When using the useEffect hook, what is the purpose of specifying dependencies in the dependency array?

Select the correct answer

question mark

What is the primary benefit of memoizing values using the useMemo hook?

Select the correct answer

Everything was clear?

How can we improve it?

Thanks for your feedback!

SectionΒ 3. ChapterΒ 13
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