有一个二维数组int[,] a= { {3，6，7}，{5，7

 int[,] a = { { 3, 6, 7 }, { 5, 7, 1 }, { 9, 4, 2 } };
            int sum = 0;
            for (int i = 0; i < a.GetLength(0); i++)
            {
                for (int j = 0; j < a.GetLength(1); j++)
                {
                    sum += a[i, j];
                    Console.Write(a[i, j] + "\t");
                }
                Console.Write(sum + "\t");
                Console.WriteLine();
                sum = 0;
            }