Reducer "index" returned undefined during initialization.

Question

ant design项目 启动报错

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Error: Reducer "index" returned undefined during initialization. If the state passed to the reducer is undefined, you must explicitly return the initial state. The initial state may not be undefined. If you don't want to set a value for this reducer, you can use null instead of undefined.

The above error occurred in the <DvaContainer> component:
    in DvaContainer

Consider adding an error boundary to your tree to customize error handling behavior.
Visit https://fb.me/react-error-boundaries to learn more about error boundaries.

Answer 1

reducer的函数参数中给state赋一个初值，即state={}