Cannot properly parse JSON Data because of its format? - json

Question

I am trying to parse data which look:
It looks like each record is sequential.. 0, 1, 2 and then within each record there are lots of key value pairs such as the name or showID.
I want to go into each record and only get certain pairs, for example the name, showID and Date.
Here is my code, I am unsure what should be my modal in for item in loop
in other words, how do I get the specific fields into my empty dictionary array?
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data
{
do
{
var jsonResult:NSDictionary = try NSJSONSerialization.JSONObjectWithData(urlContent, options: NSJSONReadingOptions.MutableContainers) as! NSDictionary
if let items = jsonResult["items"] as! NSArray?
{
var emptyArrayOfDictionary = [[String : AnyObject]]()
for item in 0...jsonResult.count
{
}
}

Answer 1

The idea would be to create a struct (or a class) which contains the properties you need, created with an initializer from the values in your dictionaries.
Let's say you want to make "Show" objects containing the show name and the show ID.
You could create a struct like this:
struct Show {
let name:String
let showID:Int
init?(dictionary: [String:AnyObject]) {
guard let name = dictionary["name"] as? String,
let showID = dictionary["showID"] as? Int else {
return nil
}
self.name = name
self.showID = showID
}
}
Then iterate over your dictionaries and pass each one to the struct initializer, something like this:
let task = NSURLSession.sharedSession().dataTaskWithURL(url) { (data, response, error) -> Void in
if let urlContent = data {
do {
if let jsonResult = try NSJSONSerialization.JSONObjectWithData(urlContent, options: []) as? [String : AnyObject] {
if let items = jsonResult["items"] as? [[String : AnyObject]] {
let shows = items.flatMap { Show(dictionary: $0) }
}
}
} catch {
print(error)
}
}
}
The struct initializer is an Optional one, meaning that if the dictionary does not contain the keys "name" or "showID" it will not create the object and will return nil instead; that's why we're using flatMap to iterate instead of map (because flatMap unwraps the Optionals).
Now you have an array of objects, shows, and you can filter or sort its contents easily with Swift methods like sort, filter, etc.
Each object in the shows array is a Show object and has name and showID properties with the data of your dictionaries.
What flatMap does is create an array of Show objects by iterating (like a loop) over the initial array. On this line:
let shows = items.flatMap { Show(dictionary: $0) }
the $0 represents the current array element. What it means is that for each element in the items array, we take it and create a new Show instance with it, and put the resulting array of objects in the constant shows.
There's also map which is often used, but here the init of our Show struct is an optional init, so it returns an Optional Show, and flatMap knows how to deal with this (it will safely unwrap the optional and ignore the nil ones) where map does not.

Answer 2

If you would like to simplify your son parsing try this Open source https://github.com/SwiftyJSON/SwiftyJSON
With this you access name field of item 0
let userName = json[0]["name"].string