响应现有请求解析JSON

Question

嗨，我有一个来自web服务的回复，我想有一个来自响应的单个url。我的答复是以下格式。

[{"cdn_streaming_uri": "9e849cfbb2e157-22558a0600b387d0abe240fe5.r73.stream..rackcdn.com", "name": "test1", "cdn_ios_uri": "d3d4c27-22558a0600b387d0abc071d0ae240kcdn.com", "cdn_ssl_uri": "https://990fea26e-22558a0600b387d0abc071d0ae240fe5.ssl.cdn.com", "cdn_enabled": false, "ttl": 259200, "log_retention": false, "cdn_uri": "99b56a009-22558a0600b3c071d0ae240fe5.r73.n.com"}, {"cdn_streaming_uri": "74ec8c-d5edc6cad91792413b1b134fde.r46.stcdn.com", "name": "test2", "cdn_ios_uri": "d05437e44-d5edc61792413b1b134fde.iosr.cdn.com", "cdn_ssl_uri": "https://a1c2ebbf5-d5edc6cd91792413b1b134fde.scdn.com", "cdn_enabled": false, "ttl": 259200, "log_retention": false, "cdn_uri": "72ffd-d5edc6ca16852413b1b134fde.cdn.com"}, {"cdn_streaming_uri": "93665b76-550971032c2a22cdn.com", "name": "test3", "cdn_ios_uri": "ca6b-550971032c2fbf19452d6a.iosr.cf2.rackcdn.com", "cdn_ssl_uri": "https://c7c39-550971032cbf19452d6cdn.com", "cdn_enabled": true, "ttl": 86400, "log_retention": true, "cdn_uri": "68fc6d831a94-550971032c252d6a.r3cdn.com"}]

我需要用"cdn_streaming_uri“来代替"test3”。

您可以在http://json.parser.online.fr/中查看JSON解析器，如何解析它？

这是我的代码：

public static object getTokenResponse(String PrivateURL, string ResponseType)
{
    HttpWebRequest request = (HttpWebRequest)WebRequest.Create(PrivateURL +"?format=JSON");
    request.Method = "GET";
    request.Headers.Add("X-Auth-Token", id);
    //request.ContentType = "application/XML";

    HttpWebResponse resp1;
    try
    {
        resp1 = (HttpWebResponse)request.GetResponse();
    }
    catch (Exception exp)
    {
        string[] st = new string[0];
        return st;
    }


    StreamReader reader = new StreamReader(resp1.GetResponseStream());
    string  secondresponse = reader.ReadToEnd();
    Console.WriteLine(secondresponse);
    reader.Close();

    JavaScriptSerializer json_serializer = new JavaScriptSerializer();
    object obj1 = json_serializer.DeserializeObject(secondresponse);
}

我可以在obj1中看到反应。

Answer 1

我认为，最好的方法是创建代表您的响应的类。最简单的方法是使用Visual的EDIT -> Paste Special -> Paste JSON As Classes选项：

​

​

您只需复制响应并将其粘贴为JSON类即可。Visual将为您生成模型。在这种情况下，结果将是：

namespace ConsoleApplication91
{
    public class Rootobject
    {
        public Class1[] Property1 { get; set; }
    }

    public class Class1
    {
        public string cdn_streaming_uri { get; set; }
        public string name { get; set; }
        public string cdn_ios_uri { get; set; }
        public string cdn_ssl_uri { get; set; }
        public bool cdn_enabled { get; set; }
        public int ttl { get; set; }
        public bool log_retention { get; set; }
        public string cdn_uri { get; set; }
    }
}

当然，这看起来不太好，但是我们总是欢迎您重构这段代码。当您拥有您的模型时，您可以下载您的响应，解析它并使用linq获取所需的内容，例如：

using (var client = new WebClient())
{
    var url = "your service url";
    var serializer = new JavaScriptSerializer();

    // Response in JSON format
    var respJson = client.DownloadString(url);

    // Deserialized response
    var resp = serializer.Deserialize<Rootobject>(respJson);

    // Your requested result
    var result = resp.Property1.FirstOrDefault(o => o.name == "test3").cdn_streaming_uri;
}

编辑：

在重构(使用DataMember属性和删除冗余模型对象)之后，您可以拥有以下模型：

[DataContract]
public class Model
{
    [DataMember(Name = "cdn_streaming_uri")]
    public string CdnStreamingUri { get; set; }

    [DataMember(Name = "name")]
    public string Name { get; set; }

    [DataMember(Name = "cdn_ios_uri")]
    public string CdnIosUri { get; set; }

    [DataMember(Name = "cdn_ssl_uri")]
    public string CdnSslUri { get; set; }

    [DataMember(Name = "cdn_enabled")]
    public bool CdnEnabled { get; set; }

    [DataMember(Name = "ttl")]
    public int Ttl { get; set; }

    [DataMember(Name = "log_retention")]
    public bool LogRetention { get; set; }

    [DataMember(Name = "cdn_uri")]
    public string CdnUri { get; set; }
}

经过一些研究，我发现JavascriptSerializer有点不受欢迎，它不支持任何类型的DataMemberAttributes。因此，我建议使用DataContractJsonSerializer。它比JavascriptSerializer稍微混乱一些，但我认为它是好的。如果您不关心任何代码约定，您可以和平地使用firs提供的选项(带有JavaScriptSerializer而没有DataMember属性)。不要忘记更新结果查询：

using (var ms = new MemoryStream(Encoding.Unicode.GetBytes(respJson)))
{
    var serializer = new DataContractJsonSerializer(typeof(Model[]));
    var resp = serializer.ReadObject(ms) as Model[];

    var result = resp.FirstOrDefault(o => o.Name == "test3").CdnStreamingUri;
}

但是，如果您不想使用linq (我仍然强烈推荐)，您可以创建一些函数来找到您需要的CdnStreamingUri：

public static class Extensions
{
    public static string GetCdnStreamingUriFor(this Model[] input, string name)
    {
        foreach (var model in input)
        {
            if (model.Name == name)
                return model.CdnStreamingUri;
        }

        return string.Empty;
    }
}

结果查询将如下所示：

var result = resp.GetCdnStreamingUriFor("test3");

P.S.所有已使用名称空间的完整列表：

using System;
using System.IO;
using System.Linq;
using System.Runtime.Serialization.Json;
using System.Text;
using System.Runtime.Serialization;

Answer 2

我建议您为该json生成类，如下面(http://json2csharp.com/ )所示：

public class RootObject
{
    public string cdn_streaming_uri { get; set; }
    public string name { get; set; }
    public string cdn_ios_uri { get; set; }
    public string cdn_ssl_uri { get; set; }
    public bool cdn_enabled { get; set; }
    public int ttl { get; set; }
    public bool log_retention { get; set; }
    public string cdn_uri { get; set; }
}

之后，可以反序列化强类型对象http://msdn.microsoft.com/en-us/library/bb355316(v=vs.110).aspx。