C# json 到数组调试“应用程序进入中断模式”

我想将 json 转换为数组，但当我尝试调试模式时，我得到“应用程序进入中断模式”，并且如果我尝试运行它，程序就会冻结。

我用的答案是将 json 转换为 C# 数组？ https://stackoverflow.com/questions/9586585/convert-json-to-a-c-sharp-array但出了点问题。

你能帮我找出错误的原因吗？

{
public class MarketHistory
{
    public string Date { get; set; }
    public string Order_Count { get; set; }
    public string Volume { get; set; }
    public string Highest { get; set; }
    public string Avarage { get; set; }
    public string Lowest { get; set; }
}

class Program
{
    public static string DownloadString(string address)
    {
        WebClient client = new WebClient();
        string reply = client.DownloadString(address);

        return reply;
    }

    static void Main(string[] args)
    {
        Console.WriteLine("Hello World!");

        string url = "https://esi.tech.ccp.is/latest/markets/10000002/history/?datasource=tranquility&type_id=42";
        var json = DownloadString(url);

        JavaScriptSerializer js = new JavaScriptSerializer();
        MarketHistory[] marketHistories = js.Deserialize<MarketHistory[]>(json);

        Console.ReadKey();
    }
}

}

json：

 [
  {
    "date": "2016-11-01",
    "order_count": 24,
    "volume": 275,
    "highest": 28.17,
    "average": 28.15,
    "lowest": 28
  },

第一个修复：

{
public class MarketHistory
{
    public string date { get; set; }
    public string order_count { get; set; }
    public string volume { get; set; }
    public string highest { get; set; }
    public string avarage { get; set; }
    public string lowest { get; set; }
}

class Program
{
    public static string DownloadString(string address)
    {
        WebClient client = new WebClient();
        string reply = client.DownloadString(address);

        return reply;
    }

    static void Main(string[] args)
    {
        Console.WriteLine("Hello World!");

        string url = "https://esi.tech.ccp.is/latest/markets/10000002/history/?datasource=tranquility&type_id=42";
        var json = DownloadString(url);

        JavaScriptSerializer js = new JavaScriptSerializer();
        MarketHistory[] marketHistories = js.Deserialize<MarketHistory[]>(json);

        Console.ReadKey();
    }
}

}

我添加了参考，知道为什么我可以获得

未处理的异常：System.IO.FileNotFoundException：无法加载文件或程序集“System.Web.Extensions，版本= 4.0.0.0，文化=中性，PublicKeyToken = 31bf3856ad364e35”。该系统找不到指定的文件。 在 Eve_console_app.Program.Main(String[] args)

error?

使用此代码并确保引用System.Runtime.Serialization dll

using System;
using System.Collections.Generic;
using System.Runtime.Serialization.Json;
namespace StackOverFlow
{
    class Program
    {
        static void Main(string[] args)
        {
            var request = System.Net.WebRequest.Create("https://esi.tech.ccp.is/latest/markets/10000002/history/?datasource=tranquility&type_id=42") as System.Net.HttpWebRequest;
            request.Method = "GET";
            request.ContentLength = 0;
            using (var response = request.GetResponse() as System.Net.HttpWebResponse)
            {
                if (response.StatusCode != System.Net.HttpStatusCode.OK)
                {
                    throw new Exception(response.StatusCode + "\t" + response.StatusDescription);
                }

                DataContractJsonSerializer jsonSerializer = new DataContractJsonSerializer(typeof(List<MarketHistory>));
                var result = jsonSerializer.ReadObject(response.GetResponseStream()) as List<MarketHistory>;
            }
            Console.ReadLine();
        }
    }

    public class MarketHistory
    {
        public string date { get; set; }
        public string order_count { get; set; }
        public string volume { get; set; }
        public string highest { get; set; }
        public string average { get; set; }
        public string lowest { get; set; }
    }
}