Does it feel like when you call this.setState or React.useState, the changes feel like it’s a step behind? Let’s dive into why this.setState and React.useStatedo not update immediately. The answer: They’re just queues React this.setState, and useState does not make changes directly ...
useState返回的函数不会立即更新状态，而是告诉React将状态更新排队，并且在所有事件处理程序都运行后完成。...
回到主题,setState可能是异步的。对此官方有这样一段描述:setState() does not always immediately update the component. It may batch or defer the update until later. This makes reading this.state right after calling setState()a potential pitfall. 关键词:batch、defer、may。 要探究setState为什么可能是...
BeacusesetStatedoes not immediately trigger an update of the state of this component in a re-render cycle. Instead it is scheduled by React and React will then perform the state update and re-render cycle when it has the resources to do that. In other words, the update could be instantly...
addMessage does not update optimisticMessage directly. If addMessage was not an async call and therefore an async transition was not needed would I still need to make the change you stated or would it work in the original order I had it. Author jsoneaday commented Sep 27, 2024 I just...
当组件首次渲染时,`useState`会将状态变量初始化为提供的初始值。此外,它还会返回一个设置器函数,该函数可用于更新状态。当状态更新时,这个设置器函数会触发组件的重新渲染。 The update process in `useState` is asynchronous, meaning that the setter function does not immediately reflect the updated state. Ins...
The useState set method is not reflecting a change immediately（16个答案）21小时前关门了。我使用...
Why state does not update immediately after you set it How event handlers access a “snapshot” of the state Setting state triggers renders You might think of your user interface as changing directly in response to the user input like a click. This may feel intuitive if you’ve beenstoryboa...
简单说下为什么React选择函数式组件，主要是class组件比较冗余、生命周期函数写法不友好，骚写法多，...
官方有这样一段描述:setState() does not always immediately update the component. It may batch or defer the update until later. This makes reading this.state right after calling setState() a potential pitfall. 从这段描述可以看出,setState函数可能是异步的。先了解下setState执行后会发生什么: ...