HTTP request and condition in Swift 2 - json

Question

I'm new in Swift and I can't find the solution to this code :
func presentationlum() {
let request = NSMutableURLRequest(URL: NSURL(string: "http://raspberrypi.local/etatlum.php")!)
let Session = NSURLSession.sharedSession()
request.HTTPMethod = "GET"
var JsonDict=NSArray()
let dem = Session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
do{
JsonDict = try! NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions(rawValue: 0) )as! NSArray
}
print(JsonDict)
})
dem.resume()
if JsonDict[0] as! String == "0"
{
print("it works !")
}
else
{
print("it works to !")
}
}
When I built it I have a "Thread 1 : signal SIGABRT" error.
The Server send a Json_encode array with only 0 or 1 ( example : ["1","0","0","1","0"]).
I just want to get this response and do conditions with it but I can't.
Please help, thanks.

Answer 1

You are accessing your answer before the blocks complete :
func presentationlum() {
let request = NSMutableURLRequest(URL: NSURL(string: "http://raspberrypi.local/etatlum.php")!)
let Session = NSURLSession.sharedSession()
request.HTTPMethod = "GET"
var JsonDict : NSArray
let dem = Session.dataTaskWithRequest(request, completionHandler: {data, response, error -> Void in
do{
if let _JsonDict = try NSJSONSerialization.JSONObjectWithData(data!, options: NSJSONReadingOptions() )as? NSArray
{
JsonDict = _JsonDict
if JsonDict[0] as! String == "0"{
print("it works !")
}else{
print("it works to !")
}
}else{
print("Cannot parse JSON answer")
}
}catch {
print("An Error as occurred : \(error)")
}
print(JsonDict)
})
dem.resume()
}