How can I parse this JSON object using Swift 3.0 - ios

Question

I'm trying to parse a JSON string returned from a new API. The returned JSON string looks like this.
QuerySearchResult":{
"StartAt":"1",
"Count":"40",
"TotalAvailable":"500",
"Items":[
{"TITLE":"OST420 Generation",
"PATH":"http:\\Test.pdf",
"WRITE":"2016-12-12T15:47:42",
"RANK":"32286574",
"SIZE":"145091",
"ISDOCUMENT":"true",
"ID":"18548",
"WPTASK":"Onsite Generation",
"WPDOCTYPE":"Local Operating Procedure",
"WPDOCREFID":"304580",
"WPCONTENTTYPE":"Document"},
{"TITLE":"OST420 Measurement",
"PATH":"http:\Test33.pdf",
.
.
I'm using the code below which accepts the JSON variable but fails when I try to load item. I've tried using Array around Dictionary but it still fails. What declaration do I need to read in Items?
if let json = try JSONSerialization.jsonObject(with: data!, options:.allowFragments) as? Dictionary<String, AnyObject> {
for item in json {
if let dict = item as? Dictionary<String, AnyObject> {
if let items = json["Items"] as? Array<Dictionary<String, AnyObject>> {
for rec in items {
if let title = rec["TITLE"] as? String {
let xx = title
}
}
}
}
}

Answer 1

First of all you are not correctly iterating through Dictionary also instead of looping through Dictionary for accessing single value, try by directly accessing it through subscripting and the proper JSON notation of Dictionary in Swift 3 is [String : Any].
if let json = try? JSONSerialization.jsonObject(with: data!, options: []) as? [String : Any],
let queryDic = json["QuerySearchResult"] as? [String : Any],
let items = queryDic["Items"] as? [[String : Any]] {
for item in items {
if let title = item["TITLE"] as? String {
print(title)
}
}
}

Answer 2

In Swift 3.1 :-
func parseJson(anyObj:AnyObject) {
if let anyObj = anyObj as? Array<Dictionary<String,AnyObject>> {
self.yourArrayName = anyObj.flatMap({yourModelName(json:$0) })
}
}

Answer 3

The Json returns the data into the dictionary and array format, so treat the json data like it, it makes you easier to understand.
Data in braces '{' and '}' is dictionary.
and Data in braces '[' or ']' is array.
Now start parsing the json data by the dictionary and array properties it exactly works. Or for confirmation print your json data.

Answer 4

Use SwiftyJSON : which can simply and easily parse the JSON more than your code.
So, how do we parse using that?
First get your response as Data()
let jsonData = JSON(data: results!)
Then here how we parse that JSON.
import Foundation
import SwiftyJSON
enum JSONParseError : ErrorType {
case UnknownField
case EmptyJSON
}
extension JSONParseError : CustomStringConvertible {
var description: String {
switch self {
case .UnknownField:
return "Error when parsing json because there is no field"
case .EmptyJSON:
return "Error when parsing empty json"
}
}
}
guard let querySearchResult : [String : JSON] = jsonData["QuerySearchResult"].dictionary else{
throw JSONParseError.UnknownField
}
guard let startAt : String = querySearchResult["StartAt"].string else{
throw JSONParseError.UnknownField
}
guard let count : String = querySearchResult["Count"].string else{
throw JSONParseError.UnknownField
}
guard let totalAvailable : String = querySearchResult["TotalAvailable"].string else{
throw JSONParseError.UnknownField
}
guard let items : [JSON] = querySearchResult["Items"].array else{
throw JSONParseError.UnknownField
}
if items.count > 0 {
for i in 0 ..< items.count{
guard let title = items[i]["TITLE"].string else{
throw JSONParseError.UnknownField
}.... //So On
}
}else{
throw JSONParseError.EmptyJSON
}