1. 定义一个函数,用来取得数字的和,但是数字的个数不确定

(1)

class Program{static int Sum(int[] array){int num = 0;for (int i = 0; i < array.Length; i++){num = num + array[i];}return num;}static void Main(string[] args){int sum = Sum(new int[]{12,13,34,5,68,9,90});Console.WriteLine(sum);}}

(2)使用参数数组

class Program{static int Plus(params int[] array)//这里定义了一个int类型的参数数组,{int num = 0;for (int i = 0; i < array.Length; i++){num = num + array[i];}return num;}static void Main(string[] args){int sum2 = Plus(1,9,2,8,3,7);//参数数组就是减少了创建数组的过程Console.WriteLine(sum2);}}