過去に教えて頂いたインデクサをアウトプット

###補足１

Javaにはない

#Program.cs

using System;
using System.Collections.Generic;

namespace IndexerLesson
{
    public class Colors
    {
        private string[] data = { "赤", "青", "黄" };
       
         //アクセス 戻り値 this[型 引数]
        public string this[int index]{
            set{
                this.data[index] = value;
            }
            get{
                return data[index];
            }
        }

    }
}

#Colors.cs

using System;
using System.Collections.Generic;

namespace IndexerLesson
{
    public class Colors
    {
        private string[] data = { "赤", "青", "黄" };

        public string this[int index]
        {
            set
            {
                this.data[index] = value;
            }
            get
            {
                return data[index];
            }
        }

    }
}

オーバーロード可能

#JMonth.cs

using System;
using System.Collections.Generic;

namespace IndexerLesson
{
    public class JMonth
    {
        private string[] months = { "睦月", "如月", "弥生", "卯月", "皐月", "水無月", "文月", "葉月", "長月", "神無月", "霜月", "師走" };
        public string this[int index]
        {
            get
            {
                return months[index - 1];
            }
        }
        public int this[string name]
        {
            get
            {
                return Array.IndexOf(months, name) + 1;
            }
        }

    }
}

#Profram.cs

using System;
using System.Collections.Generic;

namespace IndexerLesson
{
    class Class1
    {
        static void Main(string[] args)
        {
            JMonth jMonth = new JMonth();
            Console.WriteLine(jMonth[6]);
            Console.WriteLine(jMonth["神無月"]);
        }
    }
}

って認識です。