在 CoffeeScript 中，如何根据与变量匹配的另一个值从对象中获取值？

Question

我正在为我团队的 Slack 开发一个机器人，到目前为止我的搜索结果是空的。我正在从 API 中检索 JSON 对象，它 return 没问题。我想要做的是根据另一个属性是否与传递给函数的变量匹配来获取对象元素的属性的值。更详细地说，我正在尝试根据 classHash 检索 characterId。我正在尝试这个，但它不起作用。它导致 characterId 未定义。

if data.characters[0].characterBase.classHash is classHash
  characterId = data.characters[0].characterBase.characterId
else if data.characters[1].characterBase.classHash is classHash
  characterId = data.characters[1].characterBase.characterId
else if data.characters[2].characterBase.classHash is classHash
  characterId = data.characters[2].characterBase.characterId

JSON对象如下：

"characters": [
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009322984539",
                        "dateLastPlayed": "2016-07-31T02:53:56Z",
                        "minutesPlayedThisSession": "130",
                        "minutesPlayedTotal": "40010",
                        "powerLevel": 335,
                        "raceHash": 3887404748,
                        "genderHash": 3111576190,
                        "classHash": 2271682572}
                },
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009340115467",
                        "dateLastPlayed": "2016-06-22T00:28:46Z",
                        "minutesPlayedThisSession": "108",
                        "minutesPlayedTotal": "11113",
                        "powerLevel": 333,
                        "raceHash": 2803282938,
                        "genderHash": 2204441813,
                        "classHash": 671679327}
                },
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009327058547",
                        "dateLastPlayed": "2016-06-12T23:30:01Z",
                        "minutesPlayedThisSession": "62",
                        "minutesPlayedTotal": "9831",
                        "powerLevel": 334,
                        "raceHash": 898834093,
                        "genderHash": 3111576190,
                        "classHash": 3655393761}
                 }

我正在尝试获取 characters[].characterBase 的 characterId，其中 characters[].characterBase.classHash 等于传入的值。假设我传入 2271682572 作为 classHash，我想 return 与 classHash 匹配的 characterId，在本例中为 2305843009322984539

任何人都可以帮助我或指出正确的方向吗？

Answer 1

假设 characterID 是唯一的：

getCharIdByClassHash = (characters, classHash) ->
  characters.reduce(((result, char) ->
    result or # if we've already found the result, pass it thru
      (if char.characterBase.classHash is classHash
         char.characterBase.characterId
       else
         null)
  ), null)

您将取回 characterId，如果未找到匹配项，则返回 null。

示例：

getCharIdByClassHash(data.characters, 2271682572) # 2305843009322984539

编辑

这假设您的 'json' 不是

"characters": [
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009322984539",
                        "dateLastPlayed": "2016-07-31T02:53:56Z",
                        "minutesPlayedThisSession": "130",
                        "minutesPlayedTotal": "40010",
                        "powerLevel": 335,
                        "raceHash": 3887404748,
                        "genderHash": 3111576190,
                        "classHash": 2271682572,
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009340115467",
                        "dateLastPlayed": "2016-06-22T00:28:46Z",
                        "minutesPlayedThisSession": "108",
                        "minutesPlayedTotal": "11113",
                        "powerLevel": 333,
                        "raceHash": 2803282938,
                        "genderHash": 2204441813,
                        "classHash": 671679327,
                {
                    "characterBase": {

就像你写的那样

"characters": [
                {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009322984539",
                        "dateLastPlayed": "2016-07-31T02:53:56Z",
                        "minutesPlayedThisSession": "130",
                        "minutesPlayedTotal": "40010",
                        "powerLevel": 335,
                        "raceHash": 3887404748,
                        "genderHash": 3111576190,
                        "classHash": 2271682572
                    }
                }, {
                    "characterBase": {
                        "membershipId": "4611686018451933949",
                        "membershipType": 2,
                        "characterId": "2305843009340115467",
                        "dateLastPlayed": "2016-06-22T00:28:46Z",
                        "minutesPlayedThisSession": "108",
                        "minutesPlayedTotal": "11113",
                        "powerLevel": 333,
                        "raceHash": 2803282938,
                        "genderHash": 2204441813,
                        "classHash": 671679327
                    }
                }, {
                    "characterBase": {

这就是我认为你的意思。 Demo.

Answer 2

假设总有一个字符带有classHash。你可以过滤数组，弹出一个并得到它的 character

characterId = data
 .characters
 .filter (character) -> character.characterBase.classHash is classHash
 .pop()?.characterBase?.characterId

或者使用数组推导

[characterId] = (id for {characterBase: {characterId: id, classHash: hash}} in data.characters when hash is classHash)

不确定您的实际数据是什么，但这是 demo。

在 CoffeeScript 中，如何根据与变量匹配的另一个值从对象中获取值？

In CoffeeScript, how do I get a value from an object based on another value matching a variable?

coffeescript

slack

hubot

示例：

编辑