React JS，Redux状态更新中的错误，无法读取属性Symbol（Symbol.iterator）

Question

当我更新redux状态时，它给出错误TypeError：对象是不可迭代的（无法读取属性Symbol（Symbol.iterator）属性]

const initialState = {
  articles: []
};

function rootReducer(state = initialState, action) {
 switch(action.type){
   case ADD_ARTICLE:{return [...state,action.payload];}  # error occurs in this line
   default:return state;
 }
}

export default rootReducer;

Answer 1

您正在尝试克隆{}而不是[]的状态。尝试返回以下内容：

switch(action.type) {
   case ADD_ARTICLE: {
     return {
        ...state,
        action.payload
     };
   }

   default: {
     return ...state;
   }
}