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比较嵌入式数组值并获取目标值

arrays javascript

Muirik · 技术社区 · 7 年前

我正在使用以下代码检查嵌入在另一个数组中的数组是否相等:

const equal = take("services", compare(
  take("history", compare(
    (a, b) => a._id === b._id
  ))
))(obj, obj2);

const obj = {
  _id: 1,
  services: [
    {
      _id: 23,
      service: "serviceOne",
      history: [
        {
          _id: 33,
          stage: "stageOne"
        }
      ]
    },
        {
      _id: 24,
      service: "serviceTwo",
      history: [
        {
          _id: 44,
          stage: "stageOne"
        }
      ]
    },
  ]
};

const obj2 = {
  _id: 1,
  services: [
    {
      _id: 23,
      service: "serviceOne",
      history: [
        {
          _id: 33,
          stage: "stageOne"
        }
      ]
    },
        {
      _id: 24,
      service: "serviceTwo",
      history: [
        {
          _id: 45,
          stage: "stageTwo"
        },
        {
          _id: 44,
          stage: "stageOne"
        }
      ]
    },
  ]
};

上述措施正在发挥作用。当我跑的时候 console.log('equal: ', equal) 它记录 false history 大堆

const compare = cb => (a, b) => a.length === b.length && a.every((el, i) => cb(el, b[i]));
const take = (key, cb) => (a, b) => cb(a[key], b[key]);
const obj = {
  _id: 1,
  services: [{
      _id: 23,
      service: "serviceOne",
      history: [{
        _id: 33,
        stage: "stageOne"
      }]
    },
    {
      _id: 24,
      service: "serviceTwo",
      history: [{
        _id: 44,
        stage: "stageOne"
      }]
    },
  ]
};

const obj2 = {
  _id: 1,
  services: [{
      _id: 23,
      service: "serviceOne",
      history: [{
        _id: 33,
        stage: "stageOne"
      }]
    },
    {
      _id: 24,
      service: "serviceTwo",
      history: [{
          _id: 45,
          stage: "stageTwo"
        },
        {
          _id: 44,
          stage: "stageOne"
        }
      ]
    },
  ]
};
const targetService = take("services", compare(
  take("history", compare(
    (a, b) => {
      a._id === b._id;
      console.log(a);
    }
  ))
))(obj, obj2);
console.log(targetService);

在这种情况下,我如何获得“服务。服务”?根据我这里的文件,我想回去 serviceTwo ,因为它是 历史

1 回复 | 直到 7 年前

Jonas Wilms 7 年前

如果您想保留该功能模式,您可能需要添加一个 and 允许您执行多重比较的帮助器:

const compare = cb => (a, b) => a.length === b.length && a.every((el, i) => cb(el, b[i]));
const take = (key, cb) => (a, b) => cb(a[key], b[key]);
const and = (cb1, cb2) => (a, b) => cb1(a, b) && cb2(a, b);
const equals = (a, b) => a === b;

const equal = take("services", compare( 
  and(
   take("service", equals),
   take("history", compare(
     take("_id", equals)
   ))
  )
))(obj, obj2);

 const historyEquals = (a, b) =>
   a._id === b._id;

 const serviceEquals = (a, b) => 
    a.service === b.service &&
    a.history.length === b.history.length &&
    a.history.every((el, i) => historyEquals(el, b.history[i]));

 const objEquals = (a, b) =>
    a.services.length === b.services.length &&
    a.services.every((el, i) => serviceEquals(el, b.services[i]));

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