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Reactjs 减速器中的React Redux分配箭头功能警告_Reactjs_Redux_React Redux_Reducers - Fatal编程技术网

Reactjs 减速器中的React Redux分配箭头功能警告

Reactjs 减速器中的React Redux分配箭头功能警告,reactjs,redux,react-redux,reducers,Reactjs,Redux,React Redux,Reducers,有人能告诉我为什么在我的React应用程序中收到此警告吗 src/reducers/posts.js 第3:1行:在导出为模块默认值之前,为变量指定箭头函数 向函数中添加变量: export default const variable = (posts = [], action) => { switch (action.type) { case FETCH_ALL: return action.payload; case U

有人能告诉我为什么在我的React应用程序中收到此警告吗

src/reducers/posts.js 第3:1行:在导出为模块默认值之前,为变量指定箭头函数


向函数中添加变量:

export default const variable = (posts = [], action) => {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

JavaScript必须知道要导出什么

将变量添加到函数中:

export default const variable = (posts = [], action) => {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

JavaScript必须知道您要导出什么

您不能同时导出默认值和声明变量。 请尝试以下方法:

const variable = (posts = [], action) => {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

export default variable
或使用传统命名函数导出默认值:

export default function variable(posts = [], action) {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

不能同时导出默认值和声明变量。 请尝试以下方法:

const variable = (posts = [], action) => {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

export default variable
或使用传统命名函数导出默认值:

export default function variable(posts = [], action) {
    switch (action.type) {
        case FETCH_ALL:
            return action.payload;
        case UPDATE:
            return posts.map((post) => post._id === action.payload._id ? action.payload : post);
        case CREATE:
            return [ ...posts, action.payload];
        case DELETE:
            return posts.filter((post) => post._id !== action.payload);
        default:
            return posts;
    }
}

这个错误是不言自明的。将arrow函数指定给variable,然后将该变量导出为defaultWell。错误是不言自明的。将arrow函数分配给variable,然后将该变量导出为默认值,默认值可以使用对我有效的
modul.exports={variable}
!我分配了一个变量,然后在其他地方调用了解构。谢谢Roman。我得到了预期的
TS1109:表达式。
或者可以使用对我有效的
modul.exports={variable}
!我分配了一个变量,然后在其他地方调用了解构。谢谢Roman。我得到了
TS1109:预期的表达式。