React-Redux中能否直接将Action的Payload作为新Redux State？

Great question—this is a common point of confusion when working with Redux, especially when dealing with full-state replacements instead of incremental updates. Let's break this down clearly:

Can you directly use the Action Payload as the new State? #

Absolutely, and this is actually the right approach for your use case.

Here's why your concern about memory recycling isn't an issue:
When you create the payload object in your action creator (after converting the XML), you dispatch it to Redux. Once the reducer returns this payload as the new state, the Redux store will hold a reference to it. This means the garbage collector won't reclaim it—its lifecycle is now tied to the store's state, not the temporary scope of the action creator.

When would you need a deep clone? #

You only need to deep clone if the payload shares nested references with the old state (e.g., you modified part of the old state and passed that as the payload). But in your scenario, you're generating a completely new object from scratch by parsing the XML—there's no overlap with the existing state's nested data. A deep clone here would be unnecessary overhead, especially since you're dealing with large datasets.

Example Reducer Implementation #

This is how your reducer can safely handle the full-state replacement:

const initialState = {}; // Or your default initial state

const xmlDataReducer = (state = initialState, action) => {
  switch (action.type) {
    case 'FETCH_XML_SUCCESS':
      // Directly return the payload as the new state—no cloning needed
      return action.payload;
    default:
      return state;
  }
};

Key Takeaway for Your Scenario #

Since you're doing full-state updates only twice a day, replacing the entire state with the new payload is not just allowed—it's the most efficient way to handle this. You're following Redux's core rule of returning a new state reference (instead of mutating the old one), and there's no risk of the payload being prematurely recycled.

内容的提问来源于stack exchange，提问作者Yossi