.net - Is it possible to return the result of a HttpWebRequest POST method via IObservable interface -

i'm trying in single method return result of httpwebrequest post method via reactive interface iobservable. i've managed method using code below:

var request = (httpwebrequest)webrequestcreator.clienthttp.create(url);   request.method = method;   request.accept = gethttptype();   request.cookiecontainer = new cookiecontainer();     return observable.fromasyncpattern(request.begingetresponse, ar => processresponse(method, ar, request))()                     .select(r => r); 

but unsure how chain async observer of writing request stream reading of response stream required http post operation. how connect following variables obs1 & obs2 can return obs2?

var request = (httpwebrequest)webrequestcreator.clienthttp.create(url); var type = gethttptype(); request.method = method; request.accept = type; request.contenttype = type; request.cookiecontainer = new cookiecontainer();  var data = serialize(requestresource);  var obs1 = observable.fromasyncpattern(request.begingetrequeststream, ar1 => processrequest(method, data, ar1, request))  var obs2 = observable.fromasyncpattern(request.begingetresponse, ar2 => processresponse(method, ar2, request))();  // how connect obs1 , obs2 together...  return obs2; 

i have thought following should work 'processresponse' method never called, know why?

 var obs1 = observable.fromasyncpattern(request.begingetrequeststream, ar1 => processrequest(method, data, ar1, request))();  var obs2 = observable.fromasyncpattern(request.begingetresponse, ar2 => processresponse(method, ar2, request));   return obs1.selectmany(a => obs2(), (a, b) => b); 

fromasyncpattern expecting both beginaction , endaction methods arguments. think looking this:

httpwebrequest httprequest =      (httpwebrequest)httpwebrequest.create("http://www.stackoverflow.com");  httprequest.method = "post";  var requestasync = observable.fromasyncpattern<stream>(     httprequest.begingetrequeststream, httprequest.endgetrequeststream);  var responseasync = observable.fromasyncpattern<webresponse>(     httprequest.begingetresponse, httprequest.endgetresponse);  requestasync()     .selectmany(requeststream =>     {         // requeststream.write          return responseasync();     })     .subscribe(webresponse =>     {         // complete     }); 

let me know if writing request stream asynchronous , can update sample accordingly.