如何在Swift中显示来自JSON的特定数据？

大家好，我正在尝试开发一个简单的应用程序，以从Yahoo Finance获取数据。现在，我可以从yahoo获得JSON响应，但是我只需要从中获得一个数据，即股票公司名称。那么我该如何实现呢？

我的代码：

import UIKit

class ViewController: UIViewController, NSURLConnectionDelegate {

lazy var data = NSMutableData()

override func viewDidLoad() {
    super.viewDidLoad()
    startConnection()
}

    func startConnection(){
    var baseUrl:NSURL = NSURL(string:"http://query.yahooapis.com/v1/public/yql?q=select%20*%20from%20yahoo.finance.quotes%20where%20symbol%20in%20(%22PETR4.SA%22)&format=json&diagnostics=true&env=store%3A%2F%2Fdatatables.org%2Falltableswithkeys&callback=")!
    var request: NSURLRequest = NSURLRequest(URL: baseUrl)
    var connection: NSURLConnection = NSURLConnection(request: request, delegate: self, startImmediately: true)!

}

func connection(didReceiveResponse: NSURLConnection!, didReceiveResponse response: NSURLResponse!) {

    // Recieved a new request, clear out the data object
    self.data = NSMutableData()

}

func connection(connection: NSURLConnection!, didReceiveData data: NSData!) {
    // Append the recieved chunk of data to our data object
    self.data.appendData(data)
}



func connectionDidFinishLoading(connection: NSURLConnection!) {
    // Request complete, self.data should now hold the resulting info
    // Convert the retrieved data in to an object through JSON deserialization

    var err: NSError
    var jsonResult: NSDictionary = NSJSONSerialization.JSONObjectWithData(data, options: NSJSONReadingOptions.MutableContainers, error: nil) as NSDictionary

    println(jsonResult)
}
}

回复：

{
query =     {
    count = 1;
    created = "2015-01-17T04:34:11Z";
    diagnostics =         {
        "build-version" = "0.2.212";
        cache =             {
            content = 5d1e1de680846a307c9874dc3d6878dc;
            "execution-start-time" = 4;
            "execution-stop-time" = 5;
            "execution-time" = 1;
            method = GET;
            type = MEMCACHED;
        };
        javascript =             {
            "execution-start-time" = 3;
            "execution-stop-time" = 104;
            "execution-time" = 101;
            "instructions-used" = 66631;
            "table-name" = "yahoo.finance.quotes";
        };
        publiclyCallable = true;
        query =             {
            content = "select * from csv where url=@url and columns='Ask,AverageDailyVolume,Bid,AskRealtime,BidRealtime,BookValue,Change&PercentChange,Change,Commission,Currency,ChangeRealtime,AfterHoursChangeRealtime,DividendShare,LastTradeDate,TradeDate,EarningsShare,ErrorIndicationreturnedforsymbolchangedinvalid,EPSEstimateCurrentYear,EPSEstimateNextYear,EPSEstimateNextQuarter,DaysLow,DaysHigh,YearLow,YearHigh,HoldingsGainPercent,AnnualizedGain,HoldingsGain,HoldingsGainPercentRealtime,HoldingsGainRealtime,MoreInfo,OrderBookRealtime,MarketCapitalization,MarketCapRealtime,EBITDA,ChangeFromYearLow,PercentChangeFromYearLow,LastTradeRealtimeWithTime,ChangePercentRealtime,ChangeFromYearHigh,PercebtChangeFromYearHigh,LastTradeWithTime,LastTradePriceOnly,HighLimit,LowLimit,DaysRange,DaysRangeRealtime,FiftydayMovingAverage,TwoHundreddayMovingAverage,ChangeFromTwoHundreddayMovingAverage,PercentChangeFromTwoHundreddayMovingAverage,ChangeFromFiftydayMovingAverage,PercentChangeFromFiftydayMovingAverage,Name,Notes,Open,PreviousClose,PricePaid,ChangeinPercent,PriceSales,PriceBook,ExDividendDate,PERatio,DividendPayDate,PERatioRealtime,PEGRatio,PriceEPSEstimateCurrentYear,PriceEPSEstimateNextYear,Symbol,SharesOwned,ShortRatio,LastTradeTime,TickerTrend,OneyrTargetPrice,Volume,HoldingsValue,HoldingsValueRealtime,YearRange,DaysValueChange,DaysValueChangeRealtime,StockExchange,DividendYield'";
            "execution-start-time" = 5;
            "execution-stop-time" = 95;
            "execution-time" = 90;
            params = "{url=[http://download.finance.yahoo.com/d/quotes.csv?f=aa2bb2b3b4cc1c3c4c6c8dd1d2ee1e7e8e9ghjkg1g3g4g5g6ii5j1j3j4j5j6k1k2k4k5ll1l2l3mm2m3m4m5m6m7m8nn4opp1p2p5p6qrr1r2r5r6r7ss1s7t1t7t8vv1v7ww1w4xy&s=PETR4.SA]}";
        };
        "service-time" = 91;
        url =             (
                            {
                content = "http://www.datatables.org/yahoo/finance/yahoo.finance.quotes.xml";
                "execution-start-time" = 1;
                "execution-stop-time" = 1;
                "execution-time" = 0;
            },
                            {
                content = "http://download.finance.yahoo.com/d/quotes.csv?f=aa2bb2b3b4cc1c3c4c6c8dd1d2ee1e7e8e9ghjkg1g3g4g5g6ii5j1j3j4j5j6k1k2k4k5ll1l2l3mm2m3m4m5m6m7m8nn4opp1p2p5p6qrr1r2r5r6r7ss1s7t1t7t8vv1v7ww1w4xy&s=PETR4.SA";
                "execution-start-time" = 5;
                "execution-stop-time" = 95;
                "execution-time" = 90;
            }
        );
        "user-time" = 106;
    };
    lang = "en-us";
    results =         {
        quote =             {
            AfterHoursChangeRealtime = "N/A - N/A";
            AnnualizedGain = "<null>";
            Ask = "9.45";
            AskRealtime = "9.45";
            AverageDailyVolume = 80999600;
            Bid = "9.44";
            BidRealtime = "9.44";
            BookValue = "27.652";
            Change = "+0.10";
            ChangeFromFiftydayMovingAverage = "-0.9209";
            ChangeFromTwoHundreddayMovingAverage = "-7.3725";
            ChangeFromYearHigh = "-15.46";
            ChangeFromYearLow = "+1.40";
            ChangePercentRealtime = "N/A - +1.07%";
            ChangeRealtime = "+0.10";
            "Change_PercentChange" = "+0.10 - +1.07%";
            ChangeinPercent = "+1.07%";
            Commission = "<null>";
            Currency = BRL;
            DaysHigh = "9.63";
            DaysLow = "9.24";
            DaysRange = "9.24 - 9.63";
            DaysRangeRealtime = "N/A - N/A";
            DaysValueChange = "- - +1.07%";
            DaysValueChangeRealtime = "N/A - N/A";
            DividendPayDate = "<null>";
            DividendShare = "0.9672";
            DividendYield = "10.36";
            EBITDA = "66.171B";
            EPSEstimateCurrentYear = "0.00";
            EPSEstimateNextQuarter = "0.00";
            EPSEstimateNextYear = "0.00";
            EarningsShare = "1.535";
            ErrorIndicationreturnedforsymbolchangedinvalid = "<null>";
            ExDividendDate = "3-Apr-14";
            FiftydayMovingAverage = "10.3609";
            HighLimit = "<null>";
            HoldingsGain = "<null>";
            HoldingsGainPercent = "- - -";
            HoldingsGainPercentRealtime = "N/A - N/A";
            HoldingsGainRealtime = "<null>";
            HoldingsValue = "<null>";
            HoldingsValueRealtime = "<null>";
            LastTradeDate = "1/16/2015";
            LastTradePriceOnly = "9.44";
            LastTradeRealtimeWithTime = "N/A - <b>9.44</b>";
            LastTradeTime = "2:08pm";
            LastTradeWithTime = "Jan 16 - <b>9.44</b>";
            LowLimit = "<null>";
            MarketCapRealtime = "<null>";
            MarketCapitalization = "123.1B";
            MoreInfo = cnpI;
            Name = "PETROBRAS   -PN";
            Notes = "<null>";
            OneyrTargetPrice = "<null>";
            Open = "9.46";
            OrderBookRealtime = "<null>";
            PEGRatio = "<null>";
            PERatio = "6.08";
            PERatioRealtime = "<null>";
            PercebtChangeFromYearHigh = "-62.09%";
            PercentChange = "+1.07%";
            PercentChangeFromFiftydayMovingAverage = "-8.89%";
            PercentChangeFromTwoHundreddayMovingAverage = "-43.85%";
            PercentChangeFromYearLow = "+17.41%";
            PreviousClose = "9.34";
            PriceBook = "0.34";
            PriceEPSEstimateCurrentYear = "<null>";
            PriceEPSEstimateNextYear = "<null>";
            PricePaid = "<null>";
            PriceSales = "0.38";
            SharesOwned = "<null>";
            ShortRatio = "<null>";
            StockExchange = "Sao Paolo";
            Symbol = "PETR4.SA";
            TickerTrend = "&nbsp;======&nbsp;";
            TradeDate = "<null>";
            TwoHundreddayMovingAverage = "16.8125";
            Volume = 56271000;
            YearHigh = "24.90";
            YearLow = "8.04";
            YearRange = "8.04 - 24.90";
            symbol = "PETR4.SA";
        };
    };
};
}