Swift JSON Helper

EasyJSON.swift

import Foundation

//let raw = String.stringWithContentsOfURL(NSURL(string: "http://www.weather.com.cn/data/sk/101010100.html"))

struct EasyJSON {
    var _obj: AnyObject!

    init(_ obj: AnyObject) {
        //assert(NSJSONSerialization.isValidJSONObject(obj), "must be valid json object")
        _obj = obj
    }

    init(_ data: NSData) {
        var err: NSError?
        _obj = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions(), error: &err)
    }

    subscript (key: String) -> EasyJSON! {
        if let dict = _obj as? NSDictionary {
            return EasyJSON(dict[key])
        }
        return nil
    }

    subscript (index: Int) -> EasyJSON! {
        if let array = _obj as? NSArray {
            return EasyJSON(array[index])
        }
        return nil
    }

    var isObject: Bool {
        return (_obj as? NSDictionary).getLogicValue()
    }

    var isArray: Bool {
        return (_obj as? NSArray).getLogicValue()
    }

    var isNumber: Bool {
        return (_obj as? NSNumber).getLogicValue()
    }

    var isString: Bool {
        return (_obj as? String).getLogicValue()
    }

    var isBool: Bool {
        return (_obj as? Bool).getLogicValue()
    }

    @conversion @transparent func __conversion() -> String {
        return _obj as String
    }

    @conversion @transparent func __conversion() -> NSNumber {
        return _obj as NSNumber
    }

    @conversion @transparent func __conversion() -> Int? {
        if let val = _obj as? Int {
            return val
        } else if let val = _obj as? String {
           return val.toInt()
        } else {
            return nil
        }
    }
}

extension EasyJSON: LogicValue {
    @transparent func getLogicValue() -> Bool {
        if let val = _obj as? Bool {
            return val
        }
        // FIXME: logically wrong
        return false
    }
}




let raw = NSData(contentsOfURL: NSURL(string: "http://www.weather.com.cn/data/sk/101010100.html"))

var err: NSError?
let raw_obj = NSJSONSerialization.JSONObjectWithData(raw, options: NSJSONReadingOptions(), error: &err)

let obj  = EasyJSON(raw_obj)

dump(obj, name: "json")


let city: String = obj["weatherinfo"]["city"]
dump(city)

let temp: Int = obj["weatherinfo"]["temp"]!
dump(temp, name: "temperature")

      let url = NSURL.URLWithString("http://www.weather.com.cn/data/sk/101010100.html")
        var session = NSURLSession(configuration: NSURLSessionConfiguration.defaultSessionConfiguration())
        let task = session.dataTaskWithHTTPGetRequest(url) {
            (raw, resp, err) in
            NSLog("data get ok!")
            let obj = EasyJSON(raw)
            let segs = [
                obj["weatherinfo"]["city"] as String,
                obj["weatherinfo"]["temp"] as String + "℃",
                obj["weatherinfo"]["WD"] as String,
                obj["weatherinfo"]["WS"] as String,
                "湿度",
                obj["weatherinfo"]["SD"] as String,
                obj["weatherinfo"]["time"] as String]

            let weatherDescription = segs.reduce("实时:", { $0 + " " + $1 })

Cool!
Nice __conversion idea