Multidimensional Arrays - 1d) Spiral

using System;

class MatrixD
{
    static void Main()
    {
        Console.Write("Enter a size of the matrix: ");
        int n = int.Parse(Console.ReadLine());
        int[,] spiral = new int[n, n];
        int currentRow = 0;
        int currentColumn = 0;
        string direction = "down";
        for (int i = 1; i <= n*n; i++)
        {
            if (direction == "down" && (currentRow >= n || spiral[currentRow,currentColumn]!=0))
            {
                currentRow--;
                currentColumn++;
                direction = "right";
            }
            else if (direction == "right" && (currentColumn >= n || spiral[currentRow,currentColumn]!=0))
            {
                currentColumn--;
                currentRow++;
                direction = "up";
            }
            else if (direction == "up" && (currentRow > 0 || spiral[currentRow,currentColumn]!=0))
            {
                currentRow--;
                currentColumn--;
                direction = "left";
            }
            else if (direction == "left" && (currentColumn > 0 || spiral[currentRow,currentColumn]!=0))
            {
                currentColumn++;
                currentRow++;
                direction = "down";
            }

            spiral[currentRow, currentColumn] = i;

            if (direction == "down")
            {
                currentRow++;
            }
            else if (direction == "right")
            {
                currentColumn++;
            }
            else if (direction == "up")
            {
                currentRow--;
            }
            else if (direction == "left")
            {
                currentColumn--;
            }
        }
        for (int i=0; i<n; i++)
        {
            for (int j=0; j<n; j++)
            {
                Console.Write(spiral[i,j]+" ");
            }
            Console.WriteLine();
        }
    }
}