How do you use hooks with React?

React hooks are functions that let you add state and other React features to functional components, making it easier to manage component logic without using class components. They include useState for state management, useEffect for side effects, useContext for context access, and more, enabling more flexible and readable code in React applications.

In React, hooks are functions that allow you to use state and other React features in functional components... -useState Hook: useState hook allows functional components to have local state. You can declare a state variable and a function to update it. -useEffect Hook: useEffect hook allows functional components to perform side effects, such as fetching data, subscribing to events, or updating the DOM. -Custom Hooks: You can create custom hooks to reuse stateful logic across different components.

In React, we use hooks like useState for state, useEffect for side effects, and custom hooks to reuse logic, making components simpler and more efficient.

You use hooks in React to add state and lifecycle features to functional components. For example, `useState` lets you manage local state, while `useEffect` allows you to run side effects like fetching data. Hooks like `useContext` enable you to access context, and custom hooks can encapsulate reusable logic. Hooks simplify state management and improve code readability by keeping related logic together within components.

Hooks often lead to more readable code because related logic can be grouped together in a single function, making it easier to understand and maintain.

Using hooks is all about simplicity and efficiency. They streamline the development process by allowing me to reuse stateful logic across components without restructuring the entire hierarchy. Hooks also provide a more straightforward way to handle side effects, making asynchronous operations cleaner and more readable. Adopting hooks has not only enhanced my development speed but has also improved the overall structure and readability of my React applications.

- Hooks encourage organizing code based on logic, rather than lifecycle methods. This leads to more organized and maintainable components eventually. - From testing point of view we can test the behavior of a custom hook independently, and you can test individual functions that use hooks more easily. - New features and improvements are often designed with hooks in mind to help bring additional functionality and flexibility when building components. example- useTransition, useDeferredValue, useMutableSource, useId, useInsertionEffect and more.

In addition to React's built-in hooks, developers can create custom hooks to encapsulate reusable logic. Custom hooks are simply JavaScript functions that utilize one or more of React's built-in hooks. They allow for the abstraction of complex logic into reusable units, enhancing code readability, maintainability, and reusability. By leveraging custom hooks, developers can centralize common logic such as data fetching.For example, a custom hook named useFetch could encapsulate the logic for fetching data from an API, handling loading states, errors, and returning the fetched data.

It’s a great tool to keep isolated the logic from the view component. And then easier to reuse that logic in others components.

Some Best Practices while using hooks. - Avoid including state variables in the dependency array of useEffect. Instead, use a useRef to track the previous state if needed. - Extract reusable logic into custom hooks. It promotes code reusability and keeps components clean and focused to their primary purpose. - Don't call hooks inside loops, conditions, or nested functions. Placing hooks inside loops, conditions, or nested functions can lead to unexpected re-renders and side effects that are difficult to reason about. - When you call hooks at the top level of your component, React can keep track of the order and ensure that the state and effects are applied in correct sequence. - Having cleanup function when required using useEffect.

Emphasize that the order in which hooks are called matters. Hooks are called in the same order on every render, ensuring consistency in how your component behaves.

It's important to call hooks in the same order on every render to ensure that the component behaves consistently. Consistency in dependencies is crucial as it simplifies management, and following a consistent pattern makes maintaining and debugging our code easier and more efficient

useState and useEffect are fundamental hooks in React. useState allows functional components to hold and manage state. It returns an array with the current state value and a function to update it. For example, const [count, setCount] = useState(0) initializes a count state with 0. useEffect is used for side effects like data fetching or DOM manipulation. It runs after each render and ensures tasks are executed consistently. For instance, you can fetch data from an API when a component mounts. Remember, keeping hooks at the top level maintains consistency and predictability in your code.

Using React Hooks involves integrating them into your functional components to manage state, handle side effects, and interact with the component lifecycle.

Built-in hooks are the ones that are created in the fiber tree by the React team that utilize JavaScript features under the hood such as closures to add states, keep refrences, optimize DOM changes and prioritize what needs to be rendered and what can be delayed, sync something from outside with the React state, etc. You can use these hooks like useState, useReducer, useMemo, useCallback, useRef, useTransition, useEffect, useLayoutEffect, useContext, etc to compose custom hooks and build great components in you app.

The built-in hooks in React are: useState useEffect useContext useReducer useCallback useMemo useRef useImperativeHandle useLayoutEffect useDebugValue useState is used to manage state in function components. useEffect is used to perform side effects, such as fetching data or setting up subscriptions. useContext is used to access context values from function components. useReducer is used to manage state in function components using a reducer function. useCallback is used to memoize callback functions. useMemo is used to memoize the result of an expensive operation. useRef is used to access DOM elements from function components useImperativeHandle is used to expose a ref to a parent component.

Nice to know: useCallback. Functions defined inside a component are redefined each times the component renders. i.e. Placed in memory stack with a new reference. With useCallback, they are redefined only when one of its dependencies changed. On big applications with lot of components, this gain in efficiency matters. Examples: myFunction gets redefined at every render of the component: const myFunction = (arg) => {...} myFunction gets redefined only when a dependency changed. const myFunction = useCallback((arg) => {...}, [ dependency1, dependency2 ]) So if dependency1 and dependency2 didn't change, why redefine it again? It already exist in memory stack. Note that if the function as no dependency, just move it out of the component!

Nice to know useRef; In React, UseRef hook as a memory box where you may store data that you don't want to change but still want to use in the future. To interact with a DOM element in your code, for instance, you may save a reference to that element there. The data contained in useRef does not change when you update other components of your component. Think about a counter component, for instance, that has a button to increase the counter value. To update the display, you may use useRef to keep track of the counter value.

React built-in hooks: useState: Create a value that is preserved across renders and triggers a re-render when it changes. useEffect: synchronize a component with some external system. useRef: Hold a mutable value without triggering re-renders. useContext: Access values from a React context provider. useReducer: Manage complex state logic with actions. useMemo: Cache the result of a calculation between renders. useCallback: Cache a function between renders. useLayoutEffect: Like useEffect, but runs synchronously before screen paint. useSyncExternalStore: subscribe to an external store. useEffectEvent: Handle effects for events outside React.

🪛 Custom hooks are like crafting your own React tools! These functions, starting with "use," encapsulate common logic using built-in or custom hooks and return values or functions to components. For instance, a custom hook can handle API data retrieval, bundling loading, error handling, and data states, making it easily reusable across different components. 🚀

Custom hooks are JavaScript functions that leverage React’s built-in hooks to encapsulate and reuse component logic. They enable you to extract component logic into reusable functions, making your components cleaner and more manageable. A custom hook starts with the prefix 'use', adhering to React’s conventions for hooks. Determine the logic or stateful behavior you want to reuse across multiple components. This could be form handling, data fetching, or any piece of logic that involves state or side effects.

A simple demonstration of a custom hook w/ useState: import { useState } from 'react'; function useCounter(initialValue = 0) { const [count, setCount] = useState(initialValue); const increment = () => { setCount(count + 1); }; const decrement = () => { setCount(count - 1); }; const reset = () => { setCount(initialValue); }; return { count, increment, decrement, reset }; } function MyComponent() { const { count, increment, decrement, reset } = useCounter(0); return ( <div> <h1>Counter: {count}</h1> <button onClick={increment}>Increment</button> <button onClick={decrement}>Decrement</button> <button onClick={reset}>Reset</button> </div> ); } export default MyComponent;

To create custom hooks in React, define a function that starts with 'use' and uses built-in hooks or other custom hooks. This empowers you to encapsulate and reuse component logic efficiently. Code reusability at its finest!

Creating custom Hooks in React is a great way to reuse stateful logic across components. 1. Start with a Function: Create a function and name it starting with use, like useFetch. This makes it clear that it’s a Hook. 2. Use Built-in Hooks: Inside your custom Hook, use any built-in Hooks like useState or useEffect to manage state and side effects. 3. Return Values: Decide what values or functions you want to expose from your Hook. Typically, return an array or an object. 4. Handle Parameters: Allow your Hook to accept parameters to make it flexible. For example, a URL for data fetching.

Hooks have transformed React development by simplifying how we write and structure code. However, it's important to follow best practices, such as avoiding using hooks conditionally and ensuring you manage side effects carefully. This helps prevent unexpected behavior or performance issues in your app.

It’s important to use hooks judiciously, for example - it doesn't always mean using a memorisation hook will improve performance, It comes with a cost. If a computation is relatively cheap to perform or if a computation depends on props that change frequently or the memoized value is used at just 1 or 2 places it may not be worth using useMemo to memoize it.

Hook Rules: Understand and follow the rules of hooks to ensure proper usage and prevent errors. For example, hooks must be called at the top level of functional components or within other hooks. Read the React documentation: React's official documentation provides detailed explanations, examples, and best practices for using hooks effectively. Consider performance implications: Be mindful of performance considerations when using hooks, especially with effects and memoization hooks, to avoid unnecessary re-renders or performance bottlenecks. Stay updated: React evolves over time, and new hooks may be introduced in future releases. Stay informed about changes and updates to leverage the latest features and improvements in React development.

With hooks, function components gained the ability to manage state and access React lifecycle features without the need to write a Class. -> Pros : Modular, Pure, Better performance -> Cons: No hook to implement Error boundary

React hooks are tools for building dynamic web apps. Imagine a digital notepad. `useState` helps you jot down tasks, and `useEffect` acts like a reminder to show notifications when tasks are due. For example, when you add a task like "Buy groceries," `useState` stores it, and `useEffect` sets a timer to display a "Time to buy groceries!" message after 5 seconds. Hooks are like tools that make your web apps interactive and fun, similar to how real-life tools simplify daily tasks.