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Javascript Redux/React:映射到存储时调度操作_Javascript_Reactjs_Redux - Fatal编程技术网

Javascript Redux/React:映射到存储时调度操作

Javascript Redux/React:映射到存储时调度操作,javascript,reactjs,redux,Javascript,Reactjs,Redux,我有一个父组件CardList,它映射到redux存储,并为存储中找到的每个数据集呈现一个Card组件 我的问题是我无法发送操作来更新存储 我尝试在父级中分派addLine()(如下所示),也直接在Card中尝试。两者都没有执行任何操作或启动了操作,之后我遇到了一个错误无法读取未定义的属性“map” 卡片列表: (...) function CardList() { const recipes = useSelector((recipes) => recipes); const

我有一个父组件
CardList
,它映射到redux存储,并为存储中找到的每个数据集呈现一个
Card
组件

我的问题是我无法发送操作来更新存储

我尝试在父级中分派
addLine()
(如下所示),也直接在
Card
中尝试。两者都没有执行任何操作或启动了操作,之后我遇到了一个错误
无法读取未定义的属性“map”

卡片列表:

(...)

function CardList() {
  const recipes = useSelector((recipes) => recipes);
  const dispatch = useDispatch();

  return (
    <Link to='/recipe'>
      <ul>
        <section className='cardListWrapper'>
          {recipes.map((recipe) => (
            <Card
              key={recipe.id}
              recipe={recipe}
              onClick={() => dispatch(addLine())}
            />
          ))}
        </section>
      </ul>
    </Link>
  );
}

(...)

(...)

function Card({ recipe }) {
  const { title, text } = recipe;

  return (
    <div className='cardWrapper'>
      <h4 className='cardTitle'>{title}</h4>
      <p className='cardText'>{text}</p>
      <button className='cardButton'>READ MORE</button>
    </div>
  );
}

(...)
// action:

export function addLine() {
  return {
    type: "ADDLINE",
  };
}

// reducer:

function reducer(recipes = initialState, action) {
  switch (action.type) {
    case "ADDLINE":
      return console.log("this action fired");

    default:
      return recipes;
  }
}

还原程序返回了无效值。试一试


function reducer(recipes = initialState, action) {
  switch (action.type) {
    case "ADDLINE":
     // the problem was here
      console.log("this action fired");
       return recipes;

    default:
      return recipes;
  }
}

啊,我看到了我的错误,我没有返回
配方。谢谢你指给我看。