In -Out, ref traditional values issue C #

Out by value:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace_ConsoleApp1
{
	class Program
    {
    	static void Main(string[] args)
        {
            //out传值
            int number1;
            int sum = AddNumber(out number1);
            
            Console.WriteLine(number1);
            
            Console.WriteLine(sum);
            Console.ReadKey();
        }
        
        public static int AddNumber(out int num1)  //addnumber方法是用来求和的
        {
            num1 = 100;
            return num1 + 20;
        }
    }
}

Out explained by value:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace_ConsoleApp1
{
	class Program
    {
    	//out传值解释
        int num1;
        int num2 = 80;
        int numSum = Show(out num1, num2);
        Console.WriteLine(num1);
        Console.WriteLine(num2);
        //out修饰方法的参数了，那么在方法外面 可以不给这个参数赋值，但是在方法里面必须给这个out修饰符的参数赋初值
        //另外，参数加out，是吧这个方法中的参数懂得值传到方法外面去了
        //}
        public static int Show(out int number1, int number2)
        {
            number1 = 90;
            return number1 + 10;
        }
    }
}

Out of the most simple exercises:

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
namespace_ConsoleApp1
{
	class Program
    {
    	int number1;
    	int number2;
    	int sum=SumNumber(out number1,out number2);
    }
    public static int SumNumber(out int num1,out num2)
    {
    	num110;
    	num2=20;
    	return num2+num2;
    }
}

ref- traditional values

using System;

namespace 第二个视频_包
{
	class Program
    {
    	//ref的使用
        int number1 = 10;
        int number2 = 20;
        int sum = Show(ref number1, ref number2);
        Console.WriteLine("{0},{1},{2}",number1,number2,sum);
        Console.ReadKey();
     }
    //如果方法里边用ref的话主函数里边的变量必须赋初值，out不用赋初值。out可以把方法里的值传出去
    //ref，可以把值传到方法里，又可以把值传到方法外
     public static int Show(ref int num1,ref int num2)
     {
      	num1= 100;
        num2= 200;
        return num1 + num2;
     }
}

  Out, ref pretty important piece of traditional values ​​and also need to have it to conclude, so next time forgot.