C# task wait的用法

简化了 异步流程的编写 和 异常的捕获

using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.IO;
using System.Linq;
using System.Linq.Expressions;
using System.Net;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace ConsoleApp21
{
    class Program
    {

        private static async Task WriteWebRequestSizeAsync(string url)
        {
            try
            {
                WebRequest webRequest = WebRequest.Create(url);

                WebResponse response = await webRequest.GetResponseAsync();
                using (StreamReader reader = new StreamReader(
                    response.GetResponseStream()))
                {
                    string text = await reader.ReadToEndAsync();
                    Console.WriteLine(FormateBytes(text.Length));
                }
            }
            catch (WebException e)
            {

            }
            catch (IOException ei)
            {
            
            }
            catch (NotSupportedException ne)
            { 
            
            }



        }



        static void Main(string[] args)
        {

            string url= "https://www.google.com/";
            if (args.Length > 0)
            {
                url = args[0];
            }
            Console.WriteLine(url);

            Task task = WriteWebRequestSizeAsync(url);

            //指定Task 在特定的时间内完成
            // 如果在指定时间内完成则 返回 true ,否者返回false
            while (!task.Wait(100))
            {
                Console.Write(".");
            }


            Console.Read();


        }




        private static bool FormateBytes(int length)
        {
            if (length > 0)
                Console.WriteLine(length);
            else
                return false;

            return true;
            
        }
    }
}