快速检查 firebase 值是真还是假

Question

您好，我正在从 firebase 检索一些信息，我正在寻找的数据是三个子级深并且包含一个 bool 值。当我打印值时，我能够得到结果，但我无法查看结果是真还是假。

func userInfo() {

    let dbRef = FIRDatabase.database().reference()
    let stRef = FIRStorage.storage().reference()

    dbRef.child("users/\(userBiD!)").observeEventType(.Value, withBlock: { snapshot in

        let name = snapshot.value!["firstname"] as! String
        let profileImage = snapshot.value!["profilePic"] as! String
        let receivePostRequest = snapshot.value?["receivePostRequest"]

        self.nameLabel.text = name
        self.dbUserProfilePic(self.profilePhotoImageView, imageLink: profileImage)

        let receivePost = snapshot.childSnapshotForPath("receivePostRequest")

        let tags = receivePost.childSnapshotForPath("tags")

        for child in tags.children {

            /* 
            ...
            tags{
                tag1 = true
                tag2 = false

             }
            //I need to print all keys that have a true value

            */

        }

    })

}

火力地堡JSON

Answer 1

因为，根据Firebase Docs ,.children 是 . . .

An iterator for snapshots of the child nodes in this snapshot. You can use the native for..in syntax.

. . .那么您必须使用 .value 来访问他们的数据，并使用 .key 来访问他们的 key 。

因此，您可以这样做。

func userInfo() {

    let dbRef = FIRDatabase.database().reference()
    let stRef = FIRStorage.storage().reference()

    dbRef.child("users/\(userBiD!)").observeEventType(.Value, withBlock: { snapshot in

        let name = snapshot.value!["firstname"] as! String
        let profileImage = snapshot.value!["profilePic"] as! String
        let receivePostRequest = snapshot.value?["receivePostRequest"]

        self.nameLabel.text = name
        self.dbUserProfilePic(self.profilePhotoImageView, imageLink: profileImage)

        let receivePost = snapshot.childSnapshotForPath("receivePostRequest")

        let tags = receivePost.childSnapshotForPath("tags")

        for child in tags.children {
            // NEW
            if child.value == true {
                print(child.key)
            }
            // NEW
        }

    })

}

或者，如果您想将所有真值保存在一个数组中。

func userInfo() {

    let dbRef = FIRDatabase.database().reference()
    let stRef = FIRStorage.storage().reference()

    dbRef.child("users/\(userBiD!)").observeEventType(.Value, withBlock: { snapshot in

        let name = snapshot.value!["firstname"] as! String
        let profileImage = snapshot.value!["profilePic"] as! String
        let receivePostRequest = snapshot.value?["receivePostRequest"]

        self.nameLabel.text = name
        self.dbUserProfilePic(self.profilePhotoImageView, imageLink: profileImage)

        let receivePost = snapshot.childSnapshotForPath("receivePostRequest")

        let tags = receivePost.childSnapshotForPath("tags")

        for child in tags.children {
            // NEW
            var trueValues: [Bool] = []

            if child.value == true {
                trueValues.append(child.key)
            }
            // NEW
        }

    })

}