for (int x = 1; x < 8; x++)//请完善代码            {                for (int y = 1; y < 8; y++)                {                    {                        if (x == y || (x + y) == 8)                            Console.Write("o");                        else                            Console.Write(".");                    }                                 }                Console.WriteLine();            }

我帮你删掉一点代码

for(int x=1;x<8;x++)//请完善代码
            {
                for(int y=1;y<8;y++)
            {
               if(y<7)
               {
                if(x==y||(x+y)==8)
                Console.Write("o");
                else
                 Console.Write(".");
               }
               else
               {
                 if(x==y||(x+y)==8)
                Console.WriteLine("o");
                else
                 Console.WriteLine("."); 
               }