csharp IEnumberable和IEnumbrator之间的区别

Posted 2021-05-12

    class DuckTypedCount
    {
        static void PrintCount(IEnumerable collection)
        {
            dynamic d = collection;
            int count = d.Count;
            Console.WriteLine(count);
        }

        static void Main()
        {
            PrintCount(new BitArray(10));
            PrintCount(new HashSet<int> { 3, 5 });
            PrintCount(new List<int> { 1, 2, 3 });
        }
    }

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

namespace index
{
    class Program
    {
        static void GoOnIEnumberator(IEnumerator<Man> mans)
        {
            while (mans.MoveNext())
            {
                Console.WriteLine(mans.Current.age);
            }
        }
        static void Main(string[] args)
        {
            List<Man> mans = new List<Man>()
        {
            new Man
            {
               age=10,
               name="spike"
            },
            new Man
            {
                age=11,
                name="spiderMan"
            },
            new Man
            {
                age=12,
                name="ironMnan"
            },
            new Man
            {
                age=13,
                name="hulk"
            },
            new Man
            {
                age=14,
                name="wukong"
            }
        };
            //IEnumberable的用法
            //IEnumberable是IEnumberator的语法糖，让程序更短
            foreach (var item in mans)
            {
                Console.WriteLine(item.name);
            }
            //IEnumberator的用法
            //IEnumberator的与IEnumberable的最大区别就是：IEnumberator可以在函数跳转的时候
            //保存当前指针的状态
            IEnumerator<Man> manIEnumberator = mans.GetEnumerator();
            while (manIEnumberator.MoveNext())
            {
                if (manIEnumberator.Current.age > 12)
                {
                    Console.WriteLine(manIEnumberator.Current.age);
                    GoOnIEnumberator(manIEnumberator);
                }
                else
                {
                    Console.WriteLine(manIEnumberator.Current.age);
                }
            }
            Console.ReadKey();
        }
   
    }
    class Man
    {
        public int age { get; set; }
        public string name { get; set; }
    }

}