值传递和引用传递

值类型在赋值的时候，传递的是这个值的本身。
引用类型在赋值的时候，传递的是对这个对象的引用（地址）。
https://www.bilibili.com/video/BV1FJ411W7e5?p=148&spm_id_from=pageDriver


//ref 使实参和形参的地址相同 （值传递->引用传递（不占用堆地址），应该不完全对）

using System;
namespace _087_值传递和引用传递
{
    class Program
    {
        static void Main(string[] args)
        {
            //值类型：int double char decimal bool enum struct
            //引用类型：string 数组 自定义类 集合 object 接口
            //值传递和引用传递
            int n1 = 1;
            int n2 = n1;
            Console.WriteLine(n1);
            Console.WriteLine(n2);
            Console.WriteLine("==============================");
            Person p1 = new Person();
            p1.Name = "张三";
            Person p2 = p1;// 堆里，同一地址
            p2.Name = "李四";
            p1.Name = "abc";
            Person p3 = new Person();
            p3.Name = "王五";
            Console.WriteLine(p1.Name);
            Console.WriteLine(p2.Name);
            Console.WriteLine(p3.Name);
            Console.WriteLine("==============================");
            Person p = new Person();
            p.Name = "张三";
            Test(p);
            Console.WriteLine(p.Name);
            Console.WriteLine("==============================");
            //string的不可变性 每次赋值重新开辟空间
            string s1 = "张三";
            string s2 = s1;
            s2 = "李四";
            Console.WriteLine(s1);
            Console.WriteLine(s2);
            Console.WriteLine("==============================");
            //ref   使实参和形参的地址相同             （值传递->引用传递，应该不完全对）
            int number = 10;
            TestTwo(ref number);
            Console.WriteLine(number);
            Console.ReadKey();
        }
        /// <summary>
        /// 给Person类实例中的Name属性赋值
        /// </summary>
        /// <param name="pp"></param>
        public static void Test(Person pp)
        {
            Person ppp = pp;
            ppp.Name = "李四";
            //Person p = pp;
            //p.Name = "李四";
        }
        /// <summary>
        /// 给n加10
        /// </summary>
        /// <param name="n"></param>
        public static void TestTwo(ref int n)
        {
            n += 10;
        }
    }
}
using System;
using System.Collections.Generic;
using System.Text;
namespace _087_值传递和引用传递
{
    class Person
    {
        private string _name;
        public string Name { get => _name; set => _name = value; }
    }
}