reactjs / reactjs/react.dev

useReducer dispatch flow clarification

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描述

Hi,

I've been looking around to try to find out more about the "dispatch / render" flow and can not find anything relevant yet.

My question is: when I do 2 dispatchsequentially such as:

dispatch({type: ACTION_1});
dispatch({type: ACTION_2});

Are we sure that the 2 actions will be processed before the next rendering cycle occurs?
Could it be that on the next rendering cycle, only ACTION_1 has been processed then ACTION_2 is processed on a later rendering cycle?

In other words, from the react perspective, is doing:

dispatch({type: ACTION_1});
dispatch({type: ACTION_2});

equivalent to:

dispatch({type: ACTIONS: payload: [ACTION_1, ACTION2]});

In a small demo, it seems that it doesn't matter:
https://codesandbox.io/s/tzp0s (see the console messages)

In my larger react app, it seems that often time there is a render cycle between 2 consecutive dispatch.

Is it considered an anti-pattern to do 2 dispatch sequentially and should we instead do 1 dispatch with the content of the 2 dispatch combined?

Thank you!

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调研方向

未指定文档文件或测试。首先在链接的 CodeSandbox 中复现顺序 dispatch 行为,并将其与所描述的更大型应用行为进行比较;完成这项工作需要找到相关的 React 指南,并澄清 dispatch 与 render 之间的关系以及推荐的用法。

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技术栈
javascript, react
领域
documentation, frontend
Issue 类型
文档
难度
4/5
预计耗时
3-5 天
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停滞
描述清晰度
需要澄清
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