使用redux时，在调用getter方法时未定义“payload”属性

// Action Creator
const updateData = (data) => ({
  type: 'UPDATE_DATA',
  payload: data
});

// Reducer
const initialState = { data: null };
const reducer = (state = initialState, action) => {
  switch (action.type) {
    case 'UPDATE_DATA':
      if (!action.payload) {
        console.error('Payload is missing in UPDATE_DATA action');
        return state;
      }
      return { ...state, data: action.payload };
    default:
      return state;
  }
};

// 使用Redux Store
import { createStore } from 'redux';
const store = createStore(reducer);

// Dispatching an action
store.dispatch(updateData({ key: 'value' }));

// Reading the state
console.log(store.getState()); // { data: { key: 'value' } }