C # POST Request HttpWebRequest

Body is the parameter to be passed, the format "roleid=1&uid=2"
Post Cotenttype fill in:
"Application/x-www-form-urlencoded"
Soap fills in: "Text/xml; Charset=utf-8 "

        public  string posthttp (string url, string body, string contentType)         {            HttpWebRequest HttpWebRequest = (HttpWebRequest) webrequest.create (URL) ;             Httpwebrequest.contenttype = contenttype;        &NBS P   Httpwebrequest.method = "POST";            Httpwebrequest.timeout = 20000; &nbs P           byte[] Btbodys = Encoding.UTF8.GetBytes (body);            Httpwebrequest.contentlength = btbodys.length;            Httpwebrequest.getrequeststream (). Write (Btbodys, 0, Btbodys.length);             HttpWebResponse HttpWebResponse = (Http WebResponse) HttpWebRequest.GetResponse ();            StreamReader StreamReader = new StreamReader (HttpWebResponse. GetResponseStream ());            String responsecontent = Streamreader.readtoend ();              httpwebresponse.close ();            STREAMREADER.C Lose ();            Httpwebrequest.abort ();            HTTPWEBR Esponse. Close ();             return responsecontent;       }

C # POST request HttpWebRequest