using System;

using System.Text;

using System.Collections.Generic;

using System.Reflection;

​

​

using SerFunc = System.Action<System.Text.StringBuilder, object>;

​

​

class SerializerJSON

{

    private SerFunc serializer;

​

    private SerFunc createSerializerPrimitive(Type objType)

    {

        return new SerFunc((StringBuilder builder, object obj) => {

​

            builder.Append(obj.ToString());

        });

    }

​

    private SerFunc createSerializerArray(Type objType)

    {

        MethodInfo getElem = objType.GetMethod("get_Item");

        SerFunc serizalizeElem = createSerializer(getElem.ReturnType);

        return new SerFunc((StringBuilder builder, object obj) => {

            System.Collections.IEnumerable arr = (System.Collections.IEnumerable)obj;

​

            builder.Append("[");

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            int current = 0;

            foreach (var el in arr)

            {

                if (current++ != 0)

                    builder.Append(",");

​

                serizalizeElem(builder, el);

            }

​

            builder.Append("]");

        });

    }

​

    private SerFunc createSerializerMap(Type objType)

    {

        List<SerFunc> funcs = new List<SerFunc>();

​

        foreach (FieldInfo info in objType.GetFields())

        {

            SerFunc serizalizeField = createSerializer(info.FieldType);

​

            funcs.Add(new SerFunc((StringBuilder builder, object obj) => {

​

                builder.Append(info.Name);

                builder.Append(":");

                serizalizeField(builder, info.GetValue(obj));

            }));

        }

​

        return new SerFunc((StringBuilder builder, object obj) => {

​

            builder.Append("{");

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            int current = 0;

            foreach (SerFunc func in funcs)

            {

                if (current++ != 0)

                    builder.Append(",");

​

                func(builder, obj);

            }

​

            builder.Append("}");

        });

    }

    private SerFunc createSerializer(Type objType)

    {

        if (objType.IsPrimitive || objType == typeof(String))

        {

            return createSerializerPrimitive(objType);

        }

​

        if (objType.GetInterface("System.Collections.IEnumerable") != null)

        {

            return createSerializerArray(objType);

        }

​

        return createSerializerMap(objType);

    }

​

    public SerializerJSON(Type rootType)

    {

        serializer = createSerializer(rootType);

    }

​

    public String Serialize(object root)

    {

        System.Text.StringBuilder builder = new System.Text.StringBuilder(4 * 1024 * 1024);

        serializer(builder, root);

        return builder.ToString();

    }

}

​

​

class Test2

{

    public int ID;

​

    public List<int> Numbers = new List<int>();

​

    public String Name = "";

}

​

class Test

{

    public int ID;

​

    public List<int> Numbers = new List<int>();

    public Test2 MyTest2 = new Test2();

​

    private String Name;

}

​

public class Program

{

    public static void Main()

    {

        SerializerJSON ser = new SerializerJSON(typeof(Test));

        Test a = new Test();

        a.Numbers.Add(3);

        a.Numbers.Add(5);

        a.Numbers.Add(77);

        var result = ser.Serialize(a);

        System.Console.WriteLine(result);

    }

}