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introduction

In React application development, optimizing component performance is an ongoing process.useCallbackIs a React Hook that is used to memoize callback functions, ensuring that these functions remain consistent throughout the life cycle of the component, thus avoiding unnecessary rendering and performance issues.

Background

In React, a component re-renders if its props or state change. If a child component depends on the props of a parent component, and those props are functions, a new instance of the function will be created every time the parent component renders, which may cause the child components to re-render as well, even if their props have not changed in substance.

useCallbackRole

useCallbackIt is used to solve the above problems. It ensures that the function remains unchanged throughout the life cycle of the component by memoizing the callback function unless its dependencies change.

useCallbackParameter Description

useCallbackAccepts two parameters:

1. Callback: The function you wish to memoize.
2. Dependencies array: An array containing the values ​​that the function depends on. The callback function will only be recreated if one of these dependencies changes.

The basic syntax is as follows:

const memoizedCallback = useCallback(
  () =
                                   

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