fatal error: unexpectedly found nil while unwrapping an Optional value in Swift when tried to parse JSON

Question

I\'ve tried to build up a document-based Cocoa app and when I tried to parse JSON in readFromData: ofType: error: method, I got an error: fatal error: unexpec

Answer 1

If the data does not contain a valid JSON object, the JSONObjectWithData function will return a nil, so you need to do a conditional unwrapping as follows:

if let dict = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: jsonError) as? NSDictionary {
    println("Dictionary: \(dict)")
} else {
   println("nil")
   let resultString = NSString(data: data, encoding: NSUTF8StringEncoding)
   println("Flawed JSON String: \(resultString)")
}

I hope it helps..... e