json - My data is being written to Firebase database but i can't read it why? -


i'm new swift , databases. i'm trying read firebase database. i'm using example code provided here: https://www.firebase.com/docs/ios/guide/retrieving-data.html. i'm calling viewcontroller.swift file in override func viewdidload(){}

func getrootref(){         // read data , react changes         println("entered getrootref")         myrootref.observeeventtype(.value, withblock: { snapshot in             println("value1")             println(string(stringinterpolationsegment: snapshot.value))             println("value2")             }, withcancelblock: { error in                 println(error.description)                 println("error")         })         println("left getrootref") }

output:

entered getrootref left getrootref viewcontroller3 viewcontroller4 value1 (function) value2

i not understand why "(function)" printing out instead of data. both read , write permission set true. making mac app.

your code sample doesn't give enough info want - however, assuming want print out contents of myrootref node...

i believe in swift, fdatasnapshot.value considered optional - contain value or nil. therefore need unwrap value:

myrootref.observeeventtype(.value, withblock: { snapshot in         println( snapshot.value()! )           })

the ! forced unwrap of variable must contain value. should checked nil before printing or else cause runtime error.

this may safer

myrootref.observeeventtype(.value, withblock: { snapshot in     if let value: anyobject = snapshot.value() {         println(value)     }   })

note snapshot.value contain 1 of number of different objects: data types returned: * nsdictionary * nsarray * nsnumber (also includes booleans) * nsstring


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