线程取消

线程取消主要使用的是 CancellationTokenSource 对象下的CancellationToken 取消标记，

代码如下

using Microsoft.EntityFrameworkCore;
using System;
using System.Collections;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;

namespace EFCOREDB
{
    class Program
    {
        static void Main(string[] args)
        {
            Console.WriteLine("Hello World!");
            #region 线程取消
            TestThreancancel();
            #endregion
            Console.Read();
        }
        #region 线程取消
        /// <summary>
        /// 线程取消
        /// </summary>
        public static void TestThreancancel()
        {
            using CancellationTokenSource source = new CancellationTokenSource();
            ThreadPool.QueueUserWorkItem(_ => TestThreancancel1(source.Token));
            Thread.Sleep(TimeSpan.FromSeconds(3));
            source.Cancel();

            using CancellationTokenSource source1 = new CancellationTokenSource();
            ThreadPool.QueueUserWorkItem((_) => { TestThreancancel2(source1.Token); });
            //source1.CancelAfter(TimeSpan.FromSeconds(3));
            Thread.Sleep(TimeSpan.FromSeconds(3));
            source1.Cancel();

            using CancellationTokenSource source2 = new CancellationTokenSource();
            ThreadPool.QueueUserWorkItem((_) => { TestThreancancel3(source2.Token); });
            //source2.CancelAfter(TimeSpan.FromSeconds(3));
            Thread.Sleep(TimeSpan.FromSeconds(3));
            source2.Cancel();
        }

        /// <summary>
        /// 线程取消
        /// </summary>
        public static void TestThreancancel1(CancellationToken token)
        {
            Console.WriteLine($"第一个线程开始执行");
            for (int i = 0; i < 10; i++)
            {
                if (token.IsCancellationRequested)
                {
                    Console.WriteLine($"第一个线程已经取消了。。。");
                    return;
                }
                Console.WriteLine($"第一个线程TestThreancancel 输出值：{i}");
                Thread.Sleep(TimeSpan.FromSeconds(1));
                //Console.WriteLine($"第一个线程TestThreancancel 输出值：{i}");
            }
            Console.WriteLine($"第一个线程成功执行");
        }

        /// <summary>
        /// 线程取消
        /// </summary>
        public static void TestThreancancel2(CancellationToken token)
        {
            Console.WriteLine($"第二个线程开始执行");
            bool isCanceled = false;
            token.Register(() => { isCanceled = true; });
            for (int i = 0; i < 10; i++)
            {
                if (isCanceled)
                {
                    Console.WriteLine($"第二个线程已经取消了。。。");
                    return;
                }
                Console.WriteLine($"第二个线程TestThreancancel 输出值：{i}");
                Thread.Sleep(TimeSpan.FromSeconds(1));
                //Console.WriteLine($"第二个线程TestThreancancel 输出值：{i}");
            }
            Console.WriteLine($"第二个线程成功执行");
        }

        /// <summary>
        /// 线程取消
        /// </summary>
        public static void TestThreancancel3(CancellationToken token)
        {
            Console.WriteLine($"第三个线程开始执行");
            try
            {
                for (int i = 0; i < 10; i++)
                {
                    Console.WriteLine($"第三个线程TestThreancancel 输出值：{i}");
                    token.ThrowIfCancellationRequested();
                    Thread.Sleep(TimeSpan.FromSeconds(1));
                    //Console.WriteLine($"第三个线程TestThreancancel 输出值：{i}");
                }
                Console.WriteLine($"第三个线程成功执行");
            }
            catch (OperationCanceledException)
            {
                Console.WriteLine($"第三个线程已经取消了。。。");
            }
        }
        #endregion
    }
}