尝试使用 lodash 删除嵌套对象

Question

我不确定我做错了什么，但我无法取消设置。我试图从 redux 中的对象中删除一个项目。尝试使用删除，但它破坏了应用程序。我从 lodash 得到了一个真实的回应，它已被删除，但是当我在它显示相同的对象后进行控制台时。

let newState = {...state};
console.log('before', newState);
console.log(_.unset(newState, [`year2020.month${action.month}.days.day${action.day}`]));
console.log('after',newState);
return newState;

样本状态：

let state = {
  year2020: {
    month3: {
      num: 0,
      name: "January",
      length: 31,
      starts: 3,
      days: {
        day1: { mood: 1 },
        day2: { mood: 2 },
        day3: { mood: 3 },
        day11: { mood: 4 }
      }
    }
  }
};

Answer 1

由于您的路径是一个字符串（一个由点分隔的字符串），因此不要包含在数组中。

注意：使用_.cloneDeep() 而不是浅克隆（传播），因为你会改变对象的更深层次：

const state = {"year2020":{"month3":{"num":0,"name":"January","length":31,"starts":3,"days":{"day1":{"mood":1},"day2":{"mood":2},"day3":{"mood":3},"day11":{"mood":4}}}}};

const newState = _.cloneDeep(state);
const action = { payload: { month: 3, day: 1 }};
_.unset(newState, `year2020.month${action.payload.month}.days.day${action.payload.day}`);
console.log('after',newState);

<script src="https://cdnjs.cloudflare.com/ajax/libs/lodash.js/4.17.15/lodash.js"></script>

Lodash/fp 与 redux 配合得很好，因为它不会改变原始对象（在这个例子中，路径是数组）：

const state = {"year2020":{"month3":{"num":0,"name":"January","length":31,"starts":3,"days":{"day1":{"mood":1},"day2":{"mood":2},"day3":{"mood":3},"day11":{"mood":4}}}}};

const action = { payload: { month: 3, day: 1 }};

const newState = _.unset([
  'year2020',
  `month${action.payload.month}`,
  'days',
  `day${action.payload.day}`
], state);

console.log('after',newState);

<script src='https://cdn.jsdelivr.net/g/lodash@4(lodash.min.js+lodash.fp.min.js)'></script>