Question

我一直在试图弄清楚如何获取一组用户数据，并将其与其他用户数组列表进行比较，以确定它是否与它们匹配。我查看了答案here，它表明我应该构建我的数据，以便它非规范化，因此有重复。这种方法有效但我现在正在努力将这些数组存储到一个数组中，以后可以使用它。

以下是我的数据结构示例：

{
  “skills”: [
    {
      "name": "Walking"
    },
    {
      "name": "Running",
      "usersWithSkill": [
        “user1”: true,
        “user2”: true,
        “user3”: true
      ]
    },
    {
      "name": "Swimming",
      "usersWithSkill": [
        “user3”: true
      ]
    },
    {
      "name": "Dancing",
      "usersWithSkill": [
        “user1”: true,
        “user3”: true
      ]
    }
  ],
  "users": {
    "user1": {
      "firstName": "Amelia",
      "skillsList": [
        "1": true,
        "3": true
      ]
    },
    "user2": {
      "firstName": "Elena",
      "skillsList": [
        "1": true,
      ]
    },
    "user3": {
      "firstName": "John",
      "skillsList": [
        "1": true,
        "2": true,
        "3": true
      ]
    },
    “user4”: {
      "firstName": "Jack",
      "interestsList": [
        "1": true,
        "3": true
      ]
   }
  }
}

我可以查询杰克所拥有的兴趣。然而，循环发生两次，因此我很难附加一个数组来存储杰克正在寻找的用户的值。

这是我查询技能的方式：

var newArray = [String]()

func fetchSkillKeys() {

    // Loop through the array of interest keys
    for key in self.arrayOfInterestKeys {
        let interestRef = Database.database().reference(withPath: "skills/\(key)/usersSkill")
        interestRef.observeSingleEvent(of: DataEventType.value, with: { (snapshot) in
            for child in snapshot.children {
                guard let snapshot = child as? DataSnapshot else { continue }
                self.newArray.append(snapshot.key)
            }
            print(self.newArray)
        })
    }
}

这是我在控制台上打印时的数组：

[]
["0", "1", "2"]
["0", "1", "2", "0", "1", "2"]
["0", "1", "2", "0", "1", "2", "0", "1"]

当我期待类似的东西时：

["0", "1", "2", "0", "1"]

更新

回应下面的评论，arrayOfInterestKeys是从interestList获取的密钥，我在查询我想要观察的技能时将其用作参考，以下是我如何获取它们：

var arrayOfInterestKeys = [String]()

func fetchUserInterests() {

    guard let uid = Auth.auth().currentUser?.uid else { return }
    // Go to users interest list
    let databaseRef = Database.database().reference(withPath: "users/\(uid)/interestsList")

    // Observe the values
    databaseRef.observeSingleEvent(of: DataEventType.value, with: { (snapshot) in

        // Loop through the interests list
        for child in snapshot.children {
            guard let snapshot = child as? DataSnapshot else { continue }
            // Populate an empty array
            self.arrayOfInterestKeys.append(snapshot.key)
        }
   })
}

Answer 1

你有：

for child in snapshot.children {
    guard let snapshot = child as? DataSnapshot else { continue }
    self.newArray.append(snapshot.key)
}
print(self.newArray)

尝试：

for child in snapshot.children {
    let child = child as? DataSnapshot
    if let key = child?.key {
        // Make sure the key is not in the array
        if self.newArray.index(of: key) == nil {
            self.newArray.append(key)                                
        }
    }
}

此外，我想知道你打电话的方式/地点fetchSkillKeys()

使用Firebase将多个循环中的值存储到数组中。迅速

1 个答案: