static void PrintPageLength()
{
Task <int> lengthTask = AsyncTask.GetPageLengthAsync("http://csharpindepth.com");
Console.WriteLine(lengthTask.Result);
}
static void Main(string[] args)
{
new AsyncTask().DisplayWebSite();
Thread.Sleep(1000); //等待异步消息
Console.WriteLine("now get the length...");
var task = AsyncTask.MainAsync();
PrintPageLength();
task.Wait();
//任务的取消
Task t2 = AsyncTask.ThrowCancellationException();
Console.WriteLine(task.Status);
Console.WriteLine(t2.Status);
//取消的延迟操作来取消异步方法
var source = new CancellationTokenSource();
var t3 = AsyncTask.DelayFor30Seconds(source.Token);
source.CancelAfter(TimeSpan.FromSeconds(1));
Console.WriteLine("Initial satus: {0}", t3.Status);
try
{
t3.Wait();
}
catch (AggregateException e)
{
Console.WriteLine("Caught {0}", e.InnerExceptions[0]);
}
Console.WriteLine("Final Status: {0}", t3.Status);
//创建异步匿名函数
Func <Task> lambda = async() => await Task.Delay(1000);
Func <Task <int> > anonMethod = async delegate()
{
Console.WriteLine("Started");
await Task.Delay(1000);
Console.WriteLine("Finished");
return(10);
};
Console.WriteLine("start lambda...");
lambda();
Console.WriteLine("start anonMethod...");
var b = anonMethod();
Console.WriteLine(b.Result);
//使用lambda表达式创建并调用一个异步函数
Func <int, Task <int> > function = async x =>
{
Console.WriteLine("Starting... x={0}", x);
await Task.Delay(x * 1000);
Console.WriteLine("Finished... x={0}", x);
return(x * 2);
};
Task <int> first = function(5);
Task <int> second = function(3);
Console.WriteLine("First result: {0}", first.Result);
Console.WriteLine("Second result: {0}", second.Result);
Console.WriteLine("get total length");
Console.WriteLine(AsyncTask.ShowPageLengthsAsync("https://www.baidu.com", "https://www.google.com", "https://www.ithome.com").Result);
}
