先说答案是:不要把所有的方法都包上 useCallback,下面仔细讲。 代码语言:javascript 代码运行次数:0 运行 AI代码解释 const[count1,setCount1]=useState(0);const[count2,setCount2]=useState(0);consthandleClickButton1=()=>{setCount1(count1+1)};consthandleClickButton2=useCallback((...
In my experience, it's essential to consider when to steer clear of useCallback in React. While useCallback can enhance performance in certain cases, it's crucial to weigh its advantages against the complexities it introduces. Here are some scenarios where I suggest avoiding its use: Simple ...
Don't forget that useCallback() hook is called each time MyComponent renders. Even though useCallback() returns the same function object, the inline function is re-created each time (useCallback() only skips it). With useCallback() you also add more complexity to the code because you ...
上面这种写法在当前组件重新渲染时会声明一个新的handleClickButton1函数,下面useCallback里面的函数也会声明一个新的函数,被传入到useCallback中,尽管这个函数有可能因为inputs没有发生改变不会被返回到handleClickButton2变量上。 那么在我们这种情况它返回新的函数和老的函数也都一样,因为下面已经都会被渲染一下,反...
在第二篇教程中,我们将手把手带你用自定义 Hook 重构之前的组件代码,让它变得更清晰、并且可以实现逻辑复用。在重构完成之后,我们陷入了组件“不断获取数据并重新渲染”的无限循环,这时候,useCallback 站了出来,如同定海神针一般拯救了我们的应用……
在第二篇教程中,我们将手把手带你用自定义 Hook 重构之前的组件代码,让它变得更清晰、并且可以实现逻辑复用。在重构完成之后,我们陷入了组件“不断获取数据并重新渲染”的无限循环,这时候,useCallback 站了出来,如同定海神针一般拯救了我们的应用……
useCallback 源码分析 由于useCallback和useMemo实现一致,其原理都是通过areHookInputsEqual函数进行依赖项比对,区别在于useMemo返回是新数据对象,而useCallback返回是回调函数。源码如下: 代码语言:typescript AI代码解释 functionupdateCallback<T>(callback:T,deps...
Understanding useMemo and useCallback Before we discuss how and when to use these hooks, let's first understand what they are and why they were introduced. useMemo useMemois a hook that allows you to memoize (or cache) a value. It takes a function that computes a value and a dependency ...
reactjs React惯用的受控输入(useCallback、props和scope)基本上就是说，当Header组件挂载时，在Lookup中...
可以看一下这个 When to useMemo and useCallbackkentcdodds.com/blog/usememo-and-usecallback ...