class AsyncClass
{
//声明委托
private delegate int AddHandler(int a, int b);
//代理方法
public int Add(int a, int b)
{
Thread.Sleep(1000 * 3);
Console.WriteLine("ThreadID--" + Thread.CurrentThread.ManagedThreadId);
return a + b;
}
//同步调用，阻塞当前线程，顺序执行
public void Tongbu()
{
AddHandler handler = new AddHandler(Add);
int result = handler.Invoke(8, 5);
Console.WriteLine(result);
Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fffffffff"));
Console.WriteLine(handler(4, 5));
Console.WriteLine("Tongbu Done!");
}
//异步调用
public void Yibu()
{
AddHandler handler = new AddHandler(Add);
for (int i = 1; i <= 5; i++)
{
//相当于另开了5个线程去执行Add方法
IAsyncResult result = handler.BeginInvoke(i, i, new AsyncCallback(CallBack), "AsycState:OKaaa");
}
Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fffffff"));
//没有回调时也必须使用EndInvoke方法。BeginInvoke和EndInvoke必须同时出现，否则可能发生内存泄漏
//Console.WriteLine(handler.EndInvoke(result));
Console.WriteLine("Yibu Done!");
Console.ReadKey();
}
//异步回调方法
public void CallBack(IAsyncResult result)
{
//AsyncResult 是IAsyncResult接口的一个实现类，空间：System.Runtime.Remoting.Messaging
//AsyncDelegate 属性可以强制转换为用户定义的委托的实际类。
AddHandler handler = (AddHandler)((AsyncResult)result).AsyncDelegate;
Console.WriteLine(handler.EndInvoke(result));
Console.WriteLine(result.AsyncState);
Console.WriteLine("CallBack Done!");
}
//线程池
AutoResetEvent are = new AutoResetEvent(false); //信号灯
int num = 10;
public void ThreadPoolTest()
{
ThreadPool.SetMinThreads(1, 1);
ThreadPool.SetMaxThreads(5, 5);
for (int i = num; i >= 0; i--)
{
ThreadPool.QueueUserWorkItem(new WaitCallback(CallBack2),i.ToString());
}
Console.WriteLine("主线程执行！");
are.WaitOne();//阻塞当前线程，直到are执行了Set方法
Console.WriteLine("主线程结束！");
Console.ReadKey();
}
//线程池回调方法
public void CallBack2(object obj)
{
num--;
Console.WriteLine(string.Format("{0}:第{1}个线程", DateTime.Now.ToString(), obj.ToString()));
Thread.Sleep(1000);
if (num == -1)
are.Set();
}
//Task创建和运行 无返回值
public void TaskTest()
{
//方式一
Task task1 = new Task(() =>
{
Thread.Sleep(200);
Console.WriteLine("void当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
task1.Start();
//方式二
Task task2 = Task.Factory.StartNew(() =>
{
Thread.Sleep(200);
Console.WriteLine("void当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
//方式三
Task task3 = Task.Run(() =>
{
Thread.Sleep(200);
Console.WriteLine("void当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
Console.WriteLine("主线程 void");
Console.WriteLine("主线程 void Done！");
}
//Task创建和运行 有返回值
public void TaskReturnTest()
{
//方式一
Task<string> task1 = new Task<string>(() =>
{
Thread.Sleep(200);
return string.Format("当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
//task1.Start();
//方式二
Task<string> task2 = Task.Factory.StartNew<string>(() =>
{
Thread.Sleep(200);
return string.Format("当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
//方式三
Task<string> task3 = Task.Run<string>(() =>
{
Thread.Sleep(200);
return string.Format("当前线程ID = {0}", Thread.CurrentThread.ManagedThreadId);
});
task1.RunSynchronously(); //阻塞主线程，直到task1线程执行完
task2.Wait(); //等待task2执行完
Task.WaitAll(new Task[] { task1, task2, task3 }); //等待所有task执行完
Task.WaitAny(new Task[] { task1, task2, task3 }); //等待任何一个task执行完
Console.WriteLine("主线程 Return");
Console.WriteLine(task1.Result);
Console.WriteLine(task2.Result);
Console.WriteLine(task3.Result);
//至少一个task执行完，去执行后续操作
Task.WhenAny(new Task[] { task1, task2, task3 }).ContinueWith((t) =>
{
Console.WriteLine("至少有一个task执行完了。。。。。" );
});
//所有的task执行完，去执行后续操作
Task.WhenAll(new Task[] { task1, task2, task3 }).ContinueWith((t) =>
{
Console.WriteLine("所有的task都执行完了。。。。。");
});
//等同于Task.WhenAny
Task.Factory.ContinueWhenAny(new Task[] { task1, task2, task3 }, (t) =>
{
Console.WriteLine("至少有一个task执行完了。。。。。");
});
//等同于Task.WhenAll
Task.Factory.ContinueWhenAll(new Task[] { task1, task2, task3 }, (t) =>
{
Console.WriteLine("所有的task都执行完了。。。。。");
});
Console.WriteLine("主线程 Return Done！");
Console.ReadKey();
}
//Task取消任务，并设置取消任务后触发的事件
public void TaskCancelTest()
{
CancellationTokenSource source = new CancellationTokenSource();
//注册任务取消触发的事件
source.Token.Register(() =>
{
Console.WriteLine("任务已取消");
});
int index = 0;
Task task = new Task(() =>
{
while(!source.IsCancellationRequested)
{
Thread.Sleep(500);
Console.WriteLine(++index);
}
});
task.Start();
//10000毫秒后停止运行task
source.CancelAfter(10000);
Console.ReadKey();
}
//异步方法 Async、await
public static async Task<string> GetFileContentAsync(string fileName)
{
FileStream fs = new FileStream(fileName, FileMode.Open);
var bytes = new byte[fs.Length];
Console.WriteLine("开始读取文件");
int len = await fs.ReadAsync(bytes, 0, bytes.Length);
string result = Encoding.Default.GetString(bytes);
return result;
}
public static async Task GetFileContentAsync2(string fileName)
{
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
var bytes = new byte[fs.Length];
Console.WriteLine("开始读取文件");
int len = await fs.ReadAsync(bytes, 0, bytes.Length);
string result = Encoding.UTF8.GetString(bytes);
return;
}
public static async void GetFileContentAsync3(string fileName)
{
FileStream fs = new FileStream(fileName, FileMode.Open, FileAccess.Read);
var bytes = new byte[fs.Length];
Console.WriteLine("开始读取文件");
int len = await fs.ReadAsync(bytes, 0, bytes.Length);
string result = Encoding.UTF8.GetString(bytes);
}
}
一次运行结果：
image.png
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