out参数，ref参数，params参数

  1 using System;
  2 using System.Collections.Generic;
  3 using System.Linq;
  4 using System.Text;
  5 using System.Threading.Tasks;
  6
  7 namespace _07out参数
  8 {
  9     class Program
 10     {
 11         static void Main(string[] args)
 12         {
 13             //写一个方法 求一个数组中的最大值、最小值、总和、平均值
 14             int[] numbers = { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
 15             ////将要返回的4个值，放到一个数组中返回
 16
 17             //int[] res = GetMaxMinSumAvg(numbers);
 18             //Console.WriteLine("最大值是{0},最小值是{1},总和是{2},平均值是{3}", res[0], res[1], res[2], res[3]);
 19             //Console.ReadKey();
 20             int max1;
 21             int min1;
 22             int sum1;
 23             int avg1;
 24             bool b;
 25             string s;
 26             double d;
 27             Test(numbers, out max1, out min1, out sum1, out avg1, out b, out s, out d);
 28
 29             Console.WriteLine(max1);
 30             Console.WriteLine(min1);
 31             Console.WriteLine(sum1);
 32             Console.WriteLine(avg1);
 33             Console.WriteLine(b);
 34             Console.WriteLine(s);
 35             Console.WriteLine(d);
 36             Console.ReadKey();
 37
 38         }
 39         /// <summary>
 40         /// 计算一个数组的最大值、最小值、总和、平均值
 41         /// </summary>
 42         /// <param name="nums"></param>
 43         /// <returns></returns>
 44         public static int[] GetMaxMinSumAvg(int[] nums)
 45         {
 46             int[] res = new int[4];
 47             //假设 res[0] 最大值  res[1]最小值  res[2]总和  res[3]平均值
 48             res[0] = nums[0];//max
 49             res[1] = nums[0];//min
 50             res[2] = 0;//sum
 51             string name = "孙全";
 52             bool b = true;
 53             for (int i = 0; i < nums.Length; i++)
 54             {
 55                 //如果当前循环到的元素比我假定的最大值还大
 56                 if (nums[i] > res[0])
 57                 {
 58                     //将当前循环到的元素赋值给我的最大值
 59                     res[0] = nums[i];
 60                 }
 61                 if (nums[i] < res[1])
 62                 {
 63                     res[1] = nums[i];
 64                 }
 65                 res[2] += nums[i];
 66             }
 67             //平均值
 68             res[3] = res[2] / nums.Length;
 69             return res;
 70
 71
 72         }
 73
 74
 75         /// <summary>
 76         /// 计算一个整数数组的最大值、最小值、平均值、总和
 77         /// </summary>
 78         /// <param name="nums">要求值得数组</param>
 79         /// <param name="max">多余返回的最大值</param>
 80         /// <param name="min">多余返回的最小值</param>
 81         /// <param name="sum">多余返回的总和</param>
 82         /// <param name="avg">多余返回的平均值</param>
 83         public static void Test(int[] nums, out int max, out int min, out int sum, out int avg, out bool b, out string s, out double d)
 84         {
 85             //out参数要求在方法的内部必须为其赋值
 86             max = nums[0];
 87             min = nums[0];
 88             sum = 0;
 89             for (int i = 0; i < nums.Length; i++)
 90             {
 91                 if (nums[i] > max)
 92                 {
 93                     max = nums[i];
 94                 }
 95                 if (nums[i] < min)
 96                 {
 97                     min = nums[i];
 98                 }
 99                 sum += nums[i];
100             }
101             avg = sum / nums.Length;
102
103
104             b = true;
105             s = "123";
106             d = 3.13;
107         }
108
109
110
111     }
112 }

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6
 7 namespace _10ref参数
 8 {
 9     class Program
10     {
11         static void Main(string[] args)
12         {
13             double salary = 5000;
14             JiangJin(ref salary);
15             Console.WriteLine(salary);
16             Console.ReadKey();
17         }
18
19         public static void JiangJin(ref double s)
20         {
21             s += 500;
22
23         }
24
25         public static void FaKuan(double s)
26         {
27             s -= 500;
28         }
29     }
30 }

 1 using System;
 2 using System.Collections.Generic;
 3 using System.Linq;
 4 using System.Text;
 5 using System.Threading.Tasks;
 6
 7 namespace _12params可变参数
 8 {
 9     class Program
10     {
11         static void Main(string[] args)
12         {
13             //   int[] s = { 99, 88, 77 };
14             //Test("张三",99,100,100,100);
15             //Console.ReadKey();
16
17             //求任意长度数组的和 整数类型的
18             int[] nums = { 1, 2, 3, 4, 5 };
19             int sum = GetSum(8,9);
20             Console.WriteLine(sum);
21             Console.ReadKey();
22         }
23
24         public static int GetSum(params int[] n)
25         {
26             int sum = 0;
27             for (int i = 0; i < n.Length; i++)
28             {
29                 sum += n[i];
30             }
31             return sum;
32         }
33
34
35         public static void Test(string name, int id, params int[] score)
36         {
37             int sum = 0;
38
39             for (int i = 0; i < score.Length; i++)
40             {
41                 sum += score[i];
42             }
43             Console.WriteLine("{0}这次考试的总成绩是{1},学号是{2}", name, sum, id);
44         }
45     }
46 }