Question

我有一个对象，我想遍历其所有的子对象/密钥，这些子对象/密钥包含键值对＆＃34; pool：＆＃34; luxury＆＃34;＆＃39;。或者换句话说，我想迭代游泳池中的所有房间以设置新参数。在js中这样做的正确有效方法是什么？

var rooms = {
    SU01: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su01.ics",
        ics_txt : "",
    },
    SU02: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su02.ics",
        ics_txt : "",
    },
    SU03: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su03.ics",
        ics_txt : "",
    },
    SU11: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su11.ics",
        ics_txt : "",
    },
    SU12: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su12.ics",
        ics_txt : "",
    },
    ...

Answer 1

您可以使用Object.values()获取对象中的所有值，filter只保留您想要的值。

代码可能如下所示：

foreach (let room of Object.values(rooms).filter(r => r.pool == 'luxury')) {
    // Do something with room
}

Answer 2

假设这是您的数据集

const data = var rooms = {
    SU01: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su01.ics",
        ics_txt : "",
    },
    SU02: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su02.ics",
        ics_txt : "",
    },
    SU03: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su03.ics",
        ics_txt : "",
    },
    SU11: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su11.ics",
        ics_txt : "",
    },
    SU12: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su12.ics",
        ics_txt : "",
    },
};

如果返回房间的属性很重要，我们需要将它们添加到房间对象中，例如

const rooms = Object.keys(data).map(id => ({
  id,
  ...data[key],
}));

否则，我们只需拨打

即可拥有所有房间

const rooms = Object.values(data);

现在我们有了房间，我们必须过滤得到pool等于luxury

的房间

const luxuryRooms = rooms.filter(room => room.pool === 'luxury');

最后，您可以使用

添加新属性

const updatedRooms = luxuryRooms.map(room => ({
  ...room,
  newProperty: 'New Value',
}));

Answer 3

使用@Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { if(requestCode == SELECT_VIDEO_REQUEST && resultCode == RESULT_OK) { if(data.getData()!=null) { // SHOW PROGRESS new FileCopyProcess().execute(data.getData()); } else { Toast.makeText(getApplicationContext(), "Failed to select video" , Toast.LENGTH_LONG).show(); } } }：

lodash

输出：

var _ = require('lodash')

_(rooms)
    .values()
    .filter(r => r.pool == poolName)
    .value()

Answer 4

这是一个适用于大多数现代浏览器的解决方案。结果是一个新对象，在输入对象的项目上与您的过滤器匹配的新属性。

我没有使用一个过滤器对函数进行硬编码，而是创建了一个函数（addPropToFiltered()），它接受要过滤的属性/值的参数，以及用于添加新值的参数。

这会改变原始rooms对象，但也可以轻松更改以创建新对象（并按原样保留rooms）。

这个功能就像这样;

addPropToFiltered(inputObject, filterProp, filterValue, newProp, newPropValue);

对于您的特定问题，我们将其用作：

addPropToFiltered(rooms, "pool", "luxury", "newProp", "New Value");

会为符合newProp的每个房间添加New Value的新属性，其值为pool: "luxury"。

const addPropToFiltered = function(rooms, prop, filter, newProp, newValue) {
  return Object.keys(rooms).reduce(function(result, id) {
    const room = rooms[id];

    // Add new property if applicable
    if (room[prop] === filter) {
      room[newProp] = newValue;
    }

    result[id] = room;
    return result;
  }, {})
}

const rooms = {
  SU01: {
    enabled: true,
    pool: "comfort",
    ics_lnk: "https://avlblty.com/su01.ics",
    ics_txt: "",
  },
  SU02: {
    enabled: true,
    pool: "luxury",
    ics_lnk: "https://avlblty.com/su02.ics",
    ics_txt: "",
  },
  SU03: {
    enabled: true,
    pool: "luxury",
    ics_lnk: "https://avlblty.com/su03.ics",
    ics_txt: "",
  },
  SU11: {
    enabled: true,
    pool: "comfort",
    ics_lnk: "https://avlblty.com/su11.ics",
    ics_txt: "",
  },
  SU12: {
    enabled: true,
    pool: "luxury",
    ics_lnk: "https://avlblty.com/su12.ics",
    ics_txt: "",
  }
};

console.log(addPropToFiltered(rooms, "pool", "luxury", "newProp", "New Value"));

console.log(rooms)

Answer 5

以下代码是ES2015，并且明确表示它不会改变任何对象（rooms完全不受影响）：

const addProperties = (rooms, pool, properties) => Object
    .keys(rooms) // take the keys "SU01", "SU02",...
    .filter(key => rooms[key].pool === pool) // take only keys with matching pool
    .reduce((newRooms, key) => ({ ...newRooms,
             [key]: { ...rooms[key], ...properties } // add properties to room
         }), rooms); // take "rooms" and update all changed rooms, which results in "newRooms"

const rooms = {
    SU01: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su01.ics",
        ics_txt : "",
    },
    SU02: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su02.ics",
        ics_txt : "",
    },
    SU03: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su03.ics",
        ics_txt : "",
    },
    SU11: {
        enabled: true,
        pool: "comfort",
        ics_lnk : "https://avlblty.com/su11.ics",
        ics_txt : "",
    },
    SU12: {
        enabled: true,
        pool: "luxury",
        ics_lnk : "https://avlblty.com/su12.ics",
        ics_txt : "",
    }
};

const result = addProperties(rooms, "luxury", { newProperty: "new value" });

console.log(result);

如何在JS中为具有特定参数/值的子对象添加属性？

5 个答案: