using System;

using System.Collections.Generic;

using Newtonsoft.Json;

public class Program

{

    public static void Main()

    {

        var json = "{'item':{'a':[1,2,3],'b':{'e':'e1','f':'f1'}}}";

        var obj = JsonConvert.DeserializeObject<RootObject>(json);

            Console.WriteLine(obj.item.a[0]);

    }

}

​

​

class RootObject

{

    public Item item { get; set; }

}

​

class Item

{

    public string[] a { get; set; }

    public Abc b { get; set; }

}

class Abc

{

    public string e { get; set; }

    public string f { get; set; }

​

}

​

​

​