无法获取JSON的值-Swift

Question

I tried to get the value of "seed" from json response. But i am getting nil.

Json Response:

{
        "response": {
            "params": {
                "rows": "20",
                "defType": "abc",
                "seed": "381786611"
            }
        }
    }

Swift Parsing:

if let responseHeader:AnyObject = object?["response"] as? NSDictionary {
    if let t = (responseHeader["params"] as? NSDictionary){
       let t1 = t["seed"] as? String
       println("result is \(t1)") // This returns nil
     }
}

Json Parsing

 func processJsonToDictionary(object:AnyObject?) -> AnyObject?{
        if object != nil {
            if let data: AnyObject = object {
                var parseError: NSError?

                var jsonResult = NSJSONSerialization.JSONObjectWithData(object as NSData!, options: NSJSONReadingOptions.MutableContainers, error: &parseError) as? NSDictionary
                if(parseError != nil){
                    return parseError
                }
                else{
                    return jsonResult
                }
            }
        }
        return nil
    }

I am not able to get the value of t1. it always returns nil. How can i get the value.

Also, I put a breakpoint and tried to print the value of t1. But the Xcode Keeps crashing. Why?

Answer 1

I think the major problem here is only accessing a JSON object in swift.

var error: NSError?
let jsonDict = NSJSONSerialization.JSONObjectWithData(jsonData, options: nil, error: &error) as NSDictionary
let resp = jsonDict["response"] as? NSDictionary
let params = resp?["params"]?["seed"]
let seed = params!! as NSString

This is just to show you how a JSON object is accessed in swift. You can ofcourse change it according to your needs to remove unwanted Optional Chaining.

Answer 2

For easy JSON manipulation in Swift you could try this little library. It seems pretty easy and you could do this:

var dictionary: [String: AnyObject]!
if let json = NKJSON.parse(yourNSDataObject) {
    dictionary <> json[NKJSON.rootKey]
}

Answer 3

First confirm that the response which you are getting is in json format or in string format. For json parsing you can use swifty json pod