 
public class HttpServer : IDisposable 
{ 
private HttpListener listener; 
public void Start() 
{ 
listener = new HttpListener(); 
listener.Prefixes.Add("http://localhost/"); 
listener.AuthenticationSchemes = AuthenticationSchemes.IntegratedWindowsAuthentication | AuthenticationSchemes.Anonymous; 
listener.Start(); 
listener.BeginGetContext(GetContext, null); 
} 
private void GetContext(IAsyncResult ar) 
{ 
HttpListenerRequest Request; 
HttpListenerResponse Response; 
try 
{ 
HttpListenerContext ctx = listener.EndGetContext(ar); 
Request = ctx.Request; 
Response = ctx.Response; 
//setup waiting for the next request 
listener.BeginGetContext(GetContext, null); 
} 
catch (InvalidOperationException) 
{ 
return; 
} 
catch (HttpListenerException) 
{ 
return; 
} 
try 
{ 
var sw = new StreamWriter(Response.OutputStream); 
sw.Write(@"<html><body><p>你的請求已經(jīng)被截取</p></body></html>"); 
sw.Flush(); 
} 
finally 
{ 
Response.OutputStream.Flush(); 
Response.Close(); 
} 
} 
public void Dispose() 
{ 
if (listener != null) 
listener.Stop(); 
} 
} 

3：簡單解釋一下
代碼的核心就是HttpListener，通過它去偵聽一個端口，當有請求的時候BeginGetContext交給GetContext方法進行異步處理，在這個方法的內(nèi)部首先實現(xiàn)的就是重新監(jiān)聽。然后進行自己的處理。
呵呵，這段代碼有什么其他用處待考慮。