javascript - 即使未显式使用 `componentWillMount`，'componentWillMount' 警告仍可见

Question

在我的代码中，我没有任何显式使用 componentWillMount，但在运行 webpack 时我仍然看到一些警告.

react-dom.development.js:12386 Warning: componentWillMount has been renamed, and is not recommended for use. See https:/fb.me/react-unsafe-component-lifecycles for details.

• Move code with side effects to componentDidMount, and set initial state in the constructor.
• Rename componentWillMount to UNSAFE_componentWillMount to suppress this warning in non-strict mode. In React 17.x, only the UNSAFE_ name will work. To rename all deprecated lifecycles to their new names, you can run npx react-codemod rename-unsafe-lifecycles in your project source folder.

Please update the following components: foo, bar

我确实运行了建议的npx react-codemod rename-unsafe-lifecycles，但警告并没有消失，只是将其措辞更改为

react-dom.development.js:12386 Warning: componentWillMount has been renamed, and is not recommended for use. [...]

这里，foo和bar都是我们团队编写的自定义组件，以及一些外部库的组件。对 Visual Studio 解决方案的 componentWillMount 的完整搜索没有给我任何结果。有人可以向我解释一下我可能做错了什么吗？

我在 another question 阅读一条评论指出

I don't have any explicit place with componentWillMount, but I do have [...] a line of code after the constructor with state={ tabindex:0 } How do I "move" that into the constructor?

答案是写 构造函数(props) {super(props); this.state = { tabindex:0 }}。有人可以解释一下这里发生了什么事吗？我必须在代码中寻找什么样的模式？

更多详细信息

    printWarning    @   react-dom.development.js:12386
lowPriorityWarningWithoutStack  @   react-dom.development.js:12407
./node_modules/react-dom/cjs/react-dom.development.js.ReactStrictModeWarnings.flushPendingUnsafeLifecycleWarnings   @   react-dom.development.js:12577
flushRenderPhaseStrictModeWarningsInDEV @   react-dom.development.js:25641
commitRootImpl  @   react-dom.development.js:24871
unstable_runWithPriority    @   scheduler.development.js:815
runWithPriority$2   @   react-dom.development.js:12188
commitRoot  @   react-dom.development.js:24865
finishSyncRender    @   react-dom.development.js:24251
performSyncWorkOnRoot   @   react-dom.development.js:24223
scheduleUpdateOnFiber   @   react-dom.development.js:23590
scheduleRootUpdate  @   react-dom.development.js:26945
updateContainerAtExpirationTime @   react-dom.development.js:26973
updateContainer @   react-dom.development.js:27075
(anonymous) @   react-dom.development.js:27663
unbatchedUpdates    @   react-dom.development.js:24375
legacyRenderSubtreeIntoContainer    @   react-dom.development.js:27662
render  @   react-dom.development.js:27756
./src/index.tsx @   index.tsx:52
__webpack_require__ @   bootstrap:19
0   @   bundle.js:152632
__webpack_require__ @   bootstrap:19
(anonymous) @   bootstrap:83
(anonymous) @   bootstrap:83

相关

• ComponentWillMount warning
• https://reactjs.org/docs/react-component.html#componentwillmount

Answer 1

您收到此警告是因为 componentWillMount在较新的 React 版本中已弃用。如果您不使用componentWillMount无论您的库之一在哪里，它都需要更新。

如果这让您感觉好一些，您的生产版本将不会在控制台中显示这些警告。

如果您由于某种原因无法更新库，您可以尝试在控制台中输入类似 console.warn = () => {} 的内容来抑制这些错误。在您的App的顶部组件，但我不会推荐这个，因为那样你将无法使用 console.warn稍后在您的代码中。在您能够更新您的库之前，最好将它们视为一种烦恼。