using System;

using System.Collections.Generic;

public class Program

{

    public static void Main()

    {

        List<string[,]> arrayList = new List<string[,]>();

        var twoDArray = new string[5,5];

        // just a couple of items for testing, intentionally leaving some indices null as well

        twoDArray[0,0] = "a";

        twoDArray[0,1] = "b";

        twoDArray[0,2] = "c";

        twoDArray[1,0] = "d";

        twoDArray[1,1] = "e";

        twoDArray[1,2] = "f";

        arrayList.Add(twoDArray);

        arrayList.Add(twoDArray);

        foreach(var array in arrayList)

        {

            Console.WriteLine("=== Starting iterration for another array in the array list ===");

            // iterates over the array as flattened items

            foreach(var arrayItem in array)

            {

                Console.WriteLine(string.Format("Flattened iteration - value {0}", arrayItem));

            }

            // or you can iterate over the items with their indices

            for (int x = 0; x < array.GetLength(0); x += 1) 

            {

                for (int y = 0; y < array.GetLength(1); y += 1) 

                {

                    var indexedItem = array[x,y];

                    Console.WriteLine(string.Format("Indexed iteration - at index {0},{1} value {2}", x, y, indexedItem));

                }

            }

        }

    }

​

}