react runtime_error ai_generated true

类型错误：无法读取 undefined 的属性（读取 'value'）在访问 context 时

TypeError: Cannot read properties of undefined (reading 'value') when accessing context

ID: react/context-value-undefined-in-provider

其他格式: JSON · Markdown 中文 · English
94%修复率
87%置信度
1证据数
2023-05-18首次发现

版本兼容性

版本状态引入弃用备注
React 18.2.0 active — — —
React 17.0.2 active — — —

根因分析

一个组件使用 useContext 消费 context，但相应的 Provider 缺失，或者 Provider 没有提供 'value' prop，导致 context 值为 undefined。

English

A component consumes a context using useContext but the corresponding Provider is missing, or the Provider does not supply a 'value' prop, resulting in undefined context value.

generic

官方文档

https://react.dev/reference/react/useContext#providing-context

解决方案

  1. Ensure the component consuming the context is wrapped in the corresponding Provider component with a 'value' prop.
  2. Add a null/undefined check before accessing properties on the context value to provide a fallback UI or default value.

无效尝试

常见但无效的做法:

  1. 60% 失败

    If the consumer tries to access nested properties that aren't in the default value, it still throws undefined errors.

  2. 75% 失败

    Even if the Provider is present, importing a different context instance means the consumer doesn't see the provided value.