多线程---Thread理解(二)

一、Thread

NetFramework 1.0 1.1 Thread是最初版本，功能非常强大，唯一的前台线程。在System.Threading 命名空间下，包含了创建和操作线程。

二、启用线程

//ThreadStart 没有参数的委托
ThreadStart threadStart = () => Todo("ThreadMethod");

//Thread 接收一个 ThreadStart 对象的参数
Thread thread = new Thread(threadStart);

//开启线程，执行委托
thread.Start();

//ParameterizedThreadStart 带参数的委托
ParameterizedThreadStart parameterizedThreadStart = s => Todo("ThreadMethod");

//Thread 接收一个 ThreadStart 对象的参数
Thread thread = new Thread(parameterizedThreadStart);

//开启线程，执行委托
thread.Start("123");

三、暂停线程

thread.Suspend();

四、恢复暂停

thread.Resume();

五、挂起线程

thread.Abort();

六、等待线程执行完后再执行

//1.判断线程是否已经停止，如果线程已经停止，继续执行
while (thread.ThreadState!=ThreadState.Stopped)
{
    Thread.Sleep(200);
}
//2. join方法等待
thread.Join();

七、优先级  Highest：最高优先级  默认为：Normal

thread.Priority = ThreadPriority.Highest;

八、设置线程为前台线程/后台线程

thread.IsBackground = false;  //前台线程  进程关闭之后，线程必须执行完了再退出
thread.IsBackground = true;  //后台线程  进程关闭之后，线程也同时退出

九、回调，启动子线程执行动作A，不阻塞，A执行完了之后，子线程在执行动作B

        private void ThreadCallBack(ThreadStart threadStart, Action action)
        {
            ThreadStart start = new ThreadStart(() =>
            {
                threadStart.Invoke();
                action.Invoke();
            });
            new Thread(start).Start();
        }

　　　　　//调用回调方法
        ThreadStart threadStart = new ThreadStart(() =>
        {
           Thread.Sleep(2000);
           Console.WriteLine("threadStart 开始执行");
        });
        Action callBack = () =>
        {
           Console.WriteLine("子线程执行完了，在执行回调....");
        };
        ThreadCallBack(threadStart, callBack);

十、委托异步方法，并且返回执行的结果

        private Func<T> ThreadReturn<T>(Func<T> func)
        {
            T t = default(T);
            ThreadStart threadStart = () =>
            {
                t = func.Invoke();
            };
            var thread = new Thread(threadStart);
            thread.Start();

            return new Func<T>(() =>
            {
                thread.Join();
                return t;
            });
        }

　　　　　　　　　　//调用
                ThreadStart threadStart = new ThreadStart(() =>
                {
                    Thread.Sleep(2000);
                    Console.WriteLine("threadStart 开始执行");
                });
                Func<int> func = () =>
                {
                    Thread.Sleep(2000);
                    return DateTime.Now.Year;
                };

                var threadReturn = ThreadReturn(func);
                var result = threadReturn.Invoke();
                Console.WriteLine($"result={result}");

　　　　　private void Todo(string name)
        {
            Console.WriteLine($"Todo 方法开始执行....");

            long result = 0;
            for (int i = 0; i < 100000; i++)
            {
                result += i;
            }
            Thread.Sleep(500);
            Console.WriteLine($"Todo方法执行的结果：{result},名称{name}，ManagedThreadId：{Thread.CurrentThread.ManagedThreadId}");

            Console.WriteLine($"Todo 方法结束执行....");
        }