怎么样在.NET.NET通过HttpListener实现Http服务？

using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading;
using System.Web;
using System.IO;
using Newtonsoft.Json;

namespace HttpListenerApp
{
 /// <summary>
 /// HttpRequest逻辑处理
 /// </summary>
 public class HttpProvider
 {

 private static HttpListener httpFiledownload; //文件下载处理请求监听
 private static HttpListener httOtherRequest; //其他超做请求监听

 /// <summary>
 /// 开启HttpListener监听
 /// </summary>
 public static void Init()
 {
  httpFiledownload = new HttpListener(); //创建监听实例
  httpFiledownload.Prefixes.Add("http://10.0.0.217:20009/FileManageApi/Download/"); //添加监听地址 注意是以/结尾。
  httpFiledownload.Start(); //允许该监听地址接受请求的传入。
  Thread ThreadhttpFiledownload = new Thread(new ThreadStart(GethttpFiledownload)); //创建开启一个线程监听该地址得请求
  ThreadhttpFiledownload.Start();

  httOtherRequest = new HttpListener();
  httOtherRequest.Prefixes.Add("http://10.0.0.217:20009/BehaviorApi/EmailSend/"); //添加监听地址 注意是以/结尾。
  httOtherRequest.Start(); //允许该监听地址接受请求的传入。
  Thread ThreadhttOtherRequest = new Thread(new ThreadStart(GethttOtherRequest));
  ThreadhttOtherRequest.Start();
 }

 /// <summary>
 /// 执行文件下载处理请求监听行为
 /// </summary>
 public static void GethttpFiledownload()
 {
  while (true)
  {
  HttpListenerContext requestContext = httpFiledownload.GetContext(); //接受到新的请求
  try
  {
   //reecontext 为开启线程传入的 requestContext请求对象
   Thread subthread = new Thread(new ParameterizedThreadStart((reecontext) => 
   {
   Console.WriteLine("执行文件处理请求监听行为");

   var request = (HttpListenerContext)reecontext;
   var image = HttpUtility.UrlDecode(request.Request.QueryString["imgname"]); //接受GET请求过来的参数；
   string filepath = AppDomain.CurrentDomain.BaseDirectory + image;
   if (!File.Exists(filepath))
   {
    filepath = AppDomain.CurrentDomain.BaseDirectory + "default.jpg"; //下载默认图片
   }
   using (FileStream fs = new FileStream(filepath, FileMode.Open, FileAccess.Read))
   {
    byte[] buffer = new byte[fs.Length];
    fs.Read(buffer, 0, (int)fs.Length); //将文件读到缓存区
    request.Response.StatusCode = 200;
    request.Response.Headers.Add("Access-Control-Allow-Origin", "*");
    request.Response.ContentType = "image/jpg"; 
    request.Response.ContentLength64 = buffer.Length;
    var output = request.Response.OutputStream; //获取请求流
    output.Write(buffer, 0, buffer.Length); //将缓存区的字节数写入当前请求流返回
    output.Close();
   }
   }));
   subthread.Start(requestContext); //开启处理线程处理下载文件
  }
  catch (Exception ex)
  {
   try
   {
   requestContext.Response.StatusCode = 500;
   requestContext.Response.ContentType = "application/text";
   requestContext.Response.ContentEncoding = Encoding.UTF8;
   byte[] buffer = System.Text.Encoding.UTF8.GetBytes("System Error");
   //对客户端输出相应信息.
   requestContext.Response.ContentLength64 = buffer.Length;
   System.IO.Stream output = requestContext.Response.OutputStream;
   output.Write(buffer, 0, buffer.Length);
   //关闭输出流，释放相应资源
   output.Close();
   }
   catch { }
  }
  }
 }

 /// <summary>
 /// 执行其他超做请求监听行为
 /// </summary>
 public static void GethttOtherRequest()
 {
  while (true)
  {
  HttpListenerContext requestContext = httOtherRequest.GetContext(); //接受到新的请求
  try
  {
   //reecontext 为开启线程传入的 requestContext请求对象
   Thread subthread = new Thread(new ParameterizedThreadStart((reecontext) =>
   {
   Console.WriteLine("执行其他超做请求监听行为");
   var request = (HttpListenerContext)reecontext;
   var msg = HttpUtility.UrlDecode(request.Request.QueryString["behavior"]); //接受GET请求过来的参数；
   //在此处执行你需要进行的操作>>比如什么缓存数据读取，队列消息处理，邮件消息队列添加等等。

   request.Response.StatusCode = 200;
   request.Response.Headers.Add("Access-Control-Allow-Origin", "*");
   request.Response.ContentType = "application/json";
   requestContext.Response.ContentEncoding = Encoding.UTF8;
   byte[] buffer = System.Text.Encoding.UTF8.GetBytes(JsonConvert.SerializeObject(new { success = true, behavior = msg }));
   request.Response.ContentLength64 = buffer.Length;
   var output = request.Response.OutputStream;
   output.Write(buffer, 0, buffer.Length);
   output.Close();
   }));
   subthread.Start(requestContext); //开启处理线程处理下载文件
  }
  catch (Exception ex)
  {
   try
   {
   requestContext.Response.StatusCode = 500;
   requestContext.Response.ContentType = "application/text";
   requestContext.Response.ContentEncoding = Encoding.UTF8;
   byte[] buffer = System.Text.Encoding.UTF8.GetBytes("System Error");
   //对客户端输出相应信息.
   requestContext.Response.ContentLength64 = buffer.Length;
   System.IO.Stream output = requestContext.Response.OutputStream;
   output.Write(buffer, 0, buffer.Length);
   //关闭输出流，释放相应资源
   output.Close();
   }
   catch { }
  }
  }
 }
 }
}

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace HttpListenerApp
{
 class Program
 {
 static void Main(string[] args)
 {
  //开启请求监听
  HttpProvider.Init();
 }
 }
}