本文共 1724 字，大约阅读时间需要 5 分钟。

使用 async 修饰符可将方法、或指定为异步。 如果对方法或表达式使用此修饰符，则其称为异步方法 。

实例一

class Program    {        static void Main(string[] args)        {            Console.WriteLine("1.同步ThreaID：" + Thread.CurrentThread.ManagedThreadId);            RunTimeAsync();            Console.WriteLine("4.异步执行完毕ThreaID：" + Thread.CurrentThread.ManagedThreadId);            Thread.Sleep(5000);            Console.WriteLine("5.同步延迟完毕ThreaID：" + Thread.CurrentThread.ManagedThreadId);            Console.ReadKey();        }        public async static Task RunTimeAsync()        {            Console.WriteLine("2.进入异步ThreaID：" + Thread.CurrentThread.ManagedThreadId);            await Task.Delay(1000);            Console.WriteLine("3.异步执行后ThreaID：" + Thread.CurrentThread.ManagedThreadId);        }    }

在异步函数中，Await之后会自动创建出一个线程。执行结果就可以看出

实例二

public partial class Form1 : Form{    public Form1()    {        InitializeComponent();        button1.Click += button1_Click;    }    private async void button1_Click(object sender, EventArgs e)    {        await ExampleMethodAsync();        textBox1.Text += "\r\nControl returned to Click event handler.\n";    }    private async Task ExampleMethodAsync()    {        // The following line simulates a task-returning asynchronous process.        await Task.Delay(1000);    }}

实例三

public partial class Form1 : Form{    public Form1()    {        InitializeComponent();        button1.Click += async (sender, e) =>        {            await ExampleMethodAsync();            textBox1.Text += "\r\nControl returned to Click event handler.\n";        };    }    private async Task ExampleMethodAsync()    {        // The following line simulates a task-returning asynchronous process.        await Task.Delay(1000);    }}

参考：

转载地址：http://mkiii.baihongyu.com/