these days we have shared some of React's built-in hook functions, such as useRef, useMemo, useReducer, useImperativeHandle, etc. These built-in hook functions provide great convenience for our development work. In addition to the built-in Hook provided by React, how do we write our own hook functions? Custom Hook allows us to share logic among multiple components, improving code reusability and maintainability. To customize a hook function, we should follow the following rules: Custom Hook must start with use . Custom Hook must be a function, and React's Hook can be used inside the function. Custom Hook must return data or methods. the above three rules must be followed, and they are also mentioned in the official React documentation. Let's use a simple counter example to demonstrate how to customize a general hook function. 1. Define the counter hook function to extract the general logic of a counter into a custom Hook, this hook function should have the following capabilities: can get the value of the current counter; can add value to the counter through the hook function; can reduce the value of the counter through the hook function. based on these three requirements, we can implement the following custom Hook: import { useState } from 'react'; // define the return value type of custom Hook type UseCounterReturnType = [count: number, increment: () => void, decrement: () => void]; // define a custom Hook export default function useCounter(initialCount: number = 0): UseCounterReturnType { // use useState to initialize count state and setCount function const [count, setCount] = useState(initialCount); // define the…