firebase - Swift 3: FirebaseDB returning nil when child is present -


i have linked firebase app. when i'm trying read data db, data present in snapshot. when child read, returns nil.

here's code:

    func checkforduplicatescan(qrcode: string) {      dataservice.ds.ref_samples.observesingleevent(of: .value, with: { (snapshot) in          if let dict = snapshot.value as? [string:any] {             print(dict)             print(qrcode)             print(dict["\(qrcode)"])             if let sampledict = dict[qrcode] as? [string:any] {                 print(sampledict)                 if let isscanned = sampledict["scanned"] as? bool {                     if isscanned == true {                         print("already scanned")                         let alert = uialertcontroller(title: "already redeemed", message: "this offer has been redeemed you. stay tuned.", preferredstyle: uialertcontrollerstyle.alert)                         alert.addaction(uialertaction(title: "ok", style: uialertactionstyle.default, handler: { (alert) in                             self.tabbarcontroller?.selectedindex = 0                         }))                         self.present(alert, animated: true, completion: nil)                     } else {                         print("new scan")                         self.updateqrcode(qrcode: qrcode)                     }                 } else {                     print("error: can't read/find 'scanned' ")                 }             }else {                 print("error: invalid code scanned")                 let alert = uialertcontroller(title: "invalid qr code scanned", message: "the code you've scanned invalid.", preferredstyle: uialertcontrollerstyle.alert)                 alert.addaction(uialertaction(title: "ok", style: .default, handler: { (alert) in                     self.tabbarcontroller?.selectedindex = 0                 }))                 self.present(alert, animated: true, completion: nil)             }         } else {             print("error: can't dictionary snapshot value")         }     }) }

here's console log:

console log

the log:

  1. the dictionary came printing dict.
    print(dict)

  2. the 'test13' came from
    print(qrcode)

  3. the 'nil' came from
    print(dict["\(qrcode)"])

this code working of yesterday has failed today.

help me out!!

edit: data i'm trying read.

enter image description here

here's json file json file

update: looks i've found out problem here.

when run code, nothing printed.

if let newdict = dict[qrcode] as? nsdictionary {      print(newdict) }

but, when this, dict accessible.

if let newdict = dict["test10"] as? nsdictionary {      print(newdict) }

note qrcode string having value "test10"

wierd asf!! still can't figure reason behind , how rectify this.

just check, problem seems data type , not firebase data. hence, getting "error: invalid code scanned". go like:

if let value = snapshot.value as? nsdictionary {     let username = value?["username"] as? string ?? ""     etc ... }

[string:any] has caused problems me in past. anyhow, helpful provide sample of data you're trying read.


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