多线程（1-4-Task）(c#)

多线程（1-4-Task）

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

/*
 1:可以看到Task和Thread一样，位于System.Threading命名空间下;
 2:两种方式创建两个task,并让他们运行。可以看到通过构造函数创建的task,必须手动Start,而通过工厂创建的Task直接就启动了。
 */
namespace TaskUse
{
    class Program
    {
        static void Main(string[] args)
        {
            #region Task创建
            /// Task 3.0  
            /// 使用的是线程池的线程  全部是后台线程
            /// API很强大
            ///
            /// 多线程：业务是可以并发执行
            ///
            /// 千万不要在Task里面去启动Task


            //Console.WriteLine("This is Main thread ;Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId);

            //var task1 = new Task(() => { Console.WriteLine("Hello, task; Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId); });
            //task1.Start();

            //var task2 = Task.Factory.StartNew(() => { Console.WriteLine("Hello, task started by task factory ;Thread.CurrentThread.ManagedThreadId={0}",          Thread.CurrentThread.ManagedThreadId); });
            //Console.ReadLine();

            #endregion


            #region Task的生命周期
            /*
              从我们可以得出Task的简略生命周期：
               Created：表示默认初始化任务，但是“工厂创建的”实例直接跳过。
               WaitingToRun: 这种状态表示等待任务调度器分配线程给任务执行。
               RanToCompletion：任务执行完毕
            */
             var task1 = new Task(() =>
              {
                  Console.WriteLine("Begin");
                  Thread.Sleep(2000);
                  Console.WriteLine("Finished");
              });

              Console.WriteLine("Before start:"+task1.Status);
              task1.Start();
              Console.WriteLine("After start:"+task1.Status);
              task1.Wait(); //等待任务执行完成
              Console.WriteLine("After Finish:"+task1.Status);
              Console.Read();
            
                运行结果图一：
                      
            #endregion


            #region Task的任务控制
            //Task.Wait()
            //Task.WaitAll();
            //Task.WaitAny();
            //Task.ContinueWith()


            /*
            var task1 = new Task(() =>
            {
                Console.WriteLine("Task 1 Begin");
                System.Threading.Thread.Sleep(2000);
                Console.WriteLine("Task 1 Finish");
            });
            var task2 = new Task(() =>
            {
                Console.WriteLine("Task 2 Begin");
                System.Threading.Thread.Sleep(3000);
                Console.WriteLine("Task 2 Finish");
            });

            task1.Start();
            task2.Start();
           // Task.WaitAll(task1, task2);
           // Console.WriteLine("All task finished!");

            int i= Task.WaitAny(task1,task2); 返回值为已完成的任务在 tasks 数组参数中的索引，如果发生超时，则为 -1。
            Console.WriteLine("return value={0}",i);   
            Console.Read();
               
               运行结果图二：
               
            */

            //Task.ContinueWith()----就是在第一个Task完成后自动启动下一个Task，实现Task的延续
         
              //var task3 = new Task(() =>
              //{
              //    Console.WriteLine("Task 3 Begin");
              //    System.Threading.Thread.Sleep(3000);
              //    Console.WriteLine("Task 3 Finish");
              //});
              //var task4 = new Task(() =>
              //{
              //    Console.WriteLine("Task 4 Begin");
              //    System.Threading.Thread.Sleep(6000);
              //    Console.WriteLine("Task 4 Finish");
              //});

              //task3.Start();
              //task4.Start();
              //var result = task3.ContinueWith(task => {
              //    TaskStatus task4Status= task4.Status;
              //    Console.WriteLine("task3.finished");
              //    return "this is task result; task3Status=" + task.Status.ToString() + ",tak4Status=" + task4Status.ToString() + "!";
           
              //});
              //Console.WriteLine(result.Result.ToString()); //task3完成之后，开始执行后面的内容，并且取得task的返回值。
              //Console.Read();

                运行结果图三：
            

            #endregion


            #region 任务完成开启新任务

            //任务并没有提供回调事件来通知完成，它通过启用一个新任务的方式来完成类似的功能；
            //ContinueWith方法可以在一个任务完成的时候发起一个新的任务，这种方式天然就支持了任务的完成通知：可以在新任务中获取原任务的结果值
            //
          
            //Task.Factory.StartNew(() => { return "canshu"; }).ContinueWith(ss => { Console.WriteLine(ss.Result); });
            //Console.Read();
          

            //var task=Task.Factory.StartNew(()=>{return 1;});
            //Console.WriteLine(task.Result);
            //var result = task.ContinueWith(aa => { return aa.Result + 1; });
            //Console.WriteLine(result.Result);
            //Console.Read();

            #endregion


            #region TaskFactory的用法

            //Console.WriteLine("This is main Thread start----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));

            //string result = null;

           
            // TaskFactory taskFactory1 = Task.Factory; //(1)利用Tsak的静态成员
            TaskFactory taskFactory2 = new TaskFactory(); //(2)第二种方式创建TaskFactory
            //List taskList = new List();
            //taskList.Add(taskFactory2.StartNew(() => DoSomething("btnTask_Click_002")));
            //taskList.Add(taskFactory2.StartNew(() => DoSomething("btnTask_Click_001")));
            //taskList.Add(taskFactory2.StartNew(() => DoSomething("btnTask_Click_003")));
            //taskList.Add(taskFactory2.StartNew(() => DoSomething("btnTask_Click_004")));
            //taskList.Add(taskFactory2.StartNew(() => DoSomething("btnTask_Click_005")));


            //需要多线程加快速度  同时又要求全部完成后，才能返回
            //多业务操作  希望并发，但是全部完成后，才能返回
            //Task.WaitAll(taskList.ToArray()); //卡界面 （因为是主线程在等待子线程全部完成）

            //需要多线程加快速度  同时又要求某个完成后，才能返回
            //多业务操作  希望并发，但是某个完成后，才能返回
           // Task.WaitAny(taskList.ToArray()); //卡界面


            //Task task = taskFactory2.StartNew(t => DoSomething("btnTask_Click_006"), "煎饼果子").ContinueWith(t => Console.WriteLine("t.AsyncState={0}", t.AsyncState)); //这里调用的DoSomething是没有返回值的
            //Console.WriteLine("-----task.AsyncState={0}-----", task.AsyncState);


            //Task task2 = taskFactory2.StartNew(() => DoSomethingHasReturnValue("btnTask_Click_007")).ContinueWith(t => 
            //{
            //    result = t.Result;
            //    Console.WriteLine("t.Result={0}", t.Result);
            //}); //这里是有返回值

            //task2.Wait();
            //Console.WriteLine("**result={0}**",result);



            //Task intTask = taskFactory2.StartNew(()=>123);
            //int iResult = intTask.Result;

            //Console.WriteLine("This is main Thread end----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
       
            //Console.Read();


            #endregion          


            #region 将方法作为参数
            //Console.WriteLine("This is main Thread start----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));

           
            //Task.Factory.StartNew(new Action(() =>
            //{               
            //    BeginCalculate(() => {

            //        Console.WriteLine("This is action start----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
            //        for (int i = 0; i < 100; i++)
            //        {
            //            Console.WriteLine("Action_" + i + "");
            //        }

            //        Console.WriteLine("This is action end----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
            //    }); 
           
            //}));

            //Console.WriteLine("This is main Thread end----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
            //Console.Read();

            #endregion
        }

        private static void DoSomething(string name)
        {
           Console.WriteLine("*************DoSomething Start {0} ----Thread.CurrentThread.ManagedThreadId={1}---{2}**",name,Thread.CurrentThread.ManagedThreadId.ToString("00"),DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));

            long IResult=0;

            for(int i=0;i<1000;i++)
            {
              IResult+=i;
            }

            Console.WriteLine("*************DoSomething End {0} ----Thread.CurrentThread.ManagedThreadId={1}---{2}**", name, Thread.CurrentThread.ManagedThreadId.ToString("00"), DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));           
        }

        private static string DoSomethingHasReturnValue(string name)
        {
            Console.WriteLine("*************DoSomethingHasReturnValue Start {0} ----Thread.CurrentThread.ManagedThreadId={1}---{2}**", name, Thread.CurrentThread.ManagedThreadId.ToString("00"), DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));

            long IResult = 0;

            for (int i = 0; i < 1000; i++)
            {
                IResult += i;
            }
            Console.WriteLine("*************DoSomethingHasReturnValue End {0} ----Thread.CurrentThread.ManagedThreadId={1}---{2}**", name, Thread.CurrentThread.ManagedThreadId.ToString("00"), DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));
            return IResult.ToString();
        }


        private static void BeginCalculate(Action action)
        {
            Console.WriteLine("This is beginCalculate start----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
            for (int i = 0; i < 20; i++)
            {
                Console.WriteLine("BeginCalculate_" + i + "");  
            }
            Console.WriteLine("This is beginCalculate end----Thread.CurrentThread.ManagedThreadId={0}", Thread.CurrentThread.ManagedThreadId.ToString("00"));
            action();//执行委托
        }

     
    }
}

图一：

图二：

图三：