How to set variables from a Firebase snapshot (swift)

问题

I would like to grab the data from my Firebase snapshot and set it to variables in my Project. I get the data, but I don't know how to parse it so I can set them. I'm trying to do something like what SwiftyJSON does with API calls.

Here is my data structure in firebase:

Here is my function:

Here is the output in the console:

Is there any way to parse and set values from the (ls) array and set the "fromId", "text", "toId" to different variables for each node?

回答1:

Try using:-

FIRDatabase.database().reference().child("users/userID/ls").observeSingleEvent(of : .value, with : {(Snap) in 

  if let snapDict = Snap.value as? [String:AnyObject]{

      for each in snapDict{

           print("\(each.value["fromId"] as! String)")

         }
   }
})

回答2:

You should be able to cast the FIRDataSnapshot value into a [String:Any] dictionary and then access the values using the "fromId", "text", and "toId" keys and assign those values to variables.

回答3:

The easy way would be: SnapshotParser

Just implement your classes:

func main(){
    let users=SnapshotParser().parseAsList(snap: Snapshot, type: User.self)
    for user in users{
        //do something with your object
    }
}

class User: ParsableSnapshot {
    var id:String?=nil
    var email:String?=nil
    var ls:[Ls]?=nil

    required init(){}

    func bindProperties(binder: SnapshotParser.Binder) {
        binder.bindField(name: "id", field: &id)
        binder.bindField(name: "email", field: &email)
        binder.bindList(name: "ls", list: &ls)
    }
}

class Ls: ParsableSnapshot {
    var id:String?=nil
    var fromId:String?=nil
    var text:String?=nil
    var told:String?=nil

    required init(){}

    func bindProperties(binder: SnapshotParser.Binder) {
        binder.bindField(name: "id", field: &id)
        binder.bindField(name: "fromId", field: &fromId)
        binder.bindField(name: "text", field: &text)
        binder.bindField(name: "told", field: &told)
    }
}

来源：https://stackoverflow.com/questions/40200217/how-to-set-variables-from-a-firebase-snapshot-swift