C#，Task多线程

Question

有一个果篮，可以向这个果篮中放置苹果，

（通过控制台输入的数字，决定每次放到果篮中的苹果数量）

有3个孩子会从这个果篮中每次拿一个苹果吃掉，吃完后继续从果篮中拿苹果吃，

（3个孩子吃苹果分别需要3秒、2秒、4秒）

请利用Task多线程编写程序实现以下功能在控制台打印输出：

设计3个类代表3个孩子去从果篮中获取苹果；

每个孩子需要收到一个消息（苹果被第一次放置时）后，才会去果篮中拿苹果来吃；

每个孩子拿完一个苹果后，会花一定的时间来吃苹果，吃完后继续从果篮中拿苹果吃；

如果果篮空了，则每隔2秒去看下果篮中是否有苹果，有就拿来吃。

Answer 1

参考

using System;
using System.Threading;
using System.Threading.Tasks;
namespace ConsoleApp1
{
    class Child
    {
        public int eatSecond { get; set; }
        public int waitSecond { get; set; }
        public string name { get; set; }
        public event EventHandler<EventArgs> OnPlaceApple;
        public void PlaceApple()
        {
            OnPlaceApple(this, new EventArgs());
        }

        public void EatApple(Basket o)
        {
             new Task(() => {
                 while (true)
                 {
                     if (o.num == 0)
                     {
                         Console.WriteLine("已吃完，" + this.name + "等待中-" + DateTime.Now);
                         Thread.Sleep(this.waitSecond*1000);
                     }
                     else
                     {
                         int i;
                         lock (o) { i = o.num; o.num--; }

                         Console.WriteLine(this.name + "正在吃第" + i + "个苹果-"+DateTime.Now);
                         Thread.Sleep(this.eatSecond * 1000);
                     }
                 }
            }).Start();

        }

    }

    class Basket
    {
        public int num { get; set; }
    }
    class Program
    {
        static Basket basket = null;
        static void PlaceApply(object sender, EventArgs e)
        {
            var o = (Child)sender;
            o.EatApple(basket);
        }
        static void Main(string[] args)
        {
            var a = new Child { name = "A", eatSecond = 3, waitSecond = 2 };
            a.OnPlaceApple += PlaceApply;


            var b = new Child { name = "B", eatSecond = 2, waitSecond = 2 };
            b.OnPlaceApple += PlaceApply;


            var c = new Child { name = "C", eatSecond = 4, waitSecond = 2 };
            c.OnPlaceApple += PlaceApply;

            Console.Write("输入苹果数量：");
            var s = Console.ReadLine();
            var num = int.Parse(s);
            basket = new Basket { num = num };


            a.PlaceApple();
            b.PlaceApple();
            c.PlaceApple();


            new Task(() =>{ 
                Thread.Sleep(20000);
                Console.WriteLine("20s后重新设置苹果数量为20");
                lock (basket) { basket.num = 20; }
            }).Start();

            Console.ReadKey();
        }
    }
}