关于URL定向的问题

"http://smshttp.xunsai.com/dll/http/sendfordll/dll_send.php?uid=test0204&pwd=123456&rev=13761111888;&cnt=1&msg=你好&sdt=SOON&cpn=xunsaiapi";
  int   HttpResult;
  URL   url=new   URL(URLName);
  URLConnection   urlconn=url.openConnection();
  urlconn.connect();
  HttpURLConnection   httpconn=(HttpURLConnection)urlconn;  这个JAVA的我想转换成.net的不知道怎么办