C#学习2

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

namespace ConsoleAppFun
{
    internal class Program
    {
        static void Main(string[] args)
        {
            hello();
            sayHello("氨基丁酸");
            string a = returnDay();
            sayHello(a);
            int n = 10;
            addNumber(ref n);
            hello(n);
            Console.ReadKey();
        }
        static void hello(int a)
        {
            Console.WriteLine(a);
        }
        static void hello()
        {
            Console.WriteLine("hello");          
        }
        /// <summary>
        /// 有参无返回值参数
        /// </summary>
        /// <param name="name">姓名</param>
        static void sayHello(string name)
        {
            Console.WriteLine(name);  
        }
        static string returnDay() {
            int a = 1;
            string str;
            if (a == 1)
            {
                str = "早上";
            }
            else {
                str = "下午";
            }
            return str;
        
        }
        static void addNumber(ref int number)
        {
            number += 10;
        }
    }
}