using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace ConsoleApplication34
{
    internal class Program
    {

        private static void Main(string[] args)
        {
              int row, colown, n, x, y;//行号，列号，阶数，下一行号，下一列号
            colown = 0; y = colown - 1;
            int[,] hf;//二维矩阵

            while (true)//输入阶数
            {
                try
                {
                    System.Console.WriteLine("请输入幻方阶数:");
                    n = Convert.ToInt32(System.Console.ReadLine());
                    break;
                }
                catch (Exception)
                {
                    System.Console.WriteLine("请不要开玩笑，重新输入吧");
                }
            }

            //初始化
            row = n / 2; x = row - 1;
            hf = new int[n, n];
            hf[row, colown] = 1;

            //幻方
            for (int i = 2; i <= n * n; i++, x = row - 1, y = colown - 1)
            {
                x = x < 0 ? n - 1 : x;
                y = y < 0 ? n - 1 : y;
                if (hf[x, y] != 0)
                {
                    if (colown + 1 == n)
                        hf[row, 0] = i;
                    else
                        hf[row, colown + 1] = i;
                        colown = colown + 1;
                }
                else
                {
                    hf[x, y] = i;
                    row = x; colown = y;
                }
            }

            x = Weishu(n);//取n*n位数

            //输出幻方
            for (int k = 0; k < n; k++)
                for (int m = 0; m <= n; m++)
                {
                    if (m == n)
                    {
                        System.Console.WriteLine();
                        break;
                    }
                    System.Console.Write(Geshihua(hf[k, m], x) + " ");
                }
            Console.ReadKey();
        }

        /// <summary>
        /// 计算n*n位数
        /// </summary>
        /// <param name="n">阶数</param>
        /// <returns>最大位数</returns>
        public static int Weishu(int n)
        {
            return (n * n).ToString().Length;
        }

        /// <summary>
        /// 格式化输出数
        /// </summary>
        /// <param name="geshihua">输出数</param>
        /// <param name="l">最大位数</param>
        /// <returns>格式化后的数</returns>
        public static string Geshihua(int geshihua, int l)
        {
            return geshihua.ToString().PadLeft(l, '0');
        }
        }
    }

已经了解算法的规律   初始化不太明白    幻方里面  for循环里面  x=row-1 y=colown-1这里不明白    还有下面的也不懂  希望大神给添加注释