public void loginyahoo(string yahooid, string yahoopassword)
 {
     try
     {
         string yahoopge    = httphelper.getHtmlfromUrl(new Uri("https://login.yahoo.com/config/login?.done=http://answers.yahoo.com%2f&.src=knowsrch&.intl=us"));
         string splitstring = ((yahoopge.Substring(yahoopge.IndexOf("onsubmit=") + 30, yahoopge.IndexOf("form: login information") - (yahoopge.IndexOf("onsubmit=") + 60))).Replace("\n", "").Replace("\t", "").Replace("<input type=\"hidden\" name=", "&").Replace(">", "").Replace("value", "").Replace("\"", "") + "&login="******"&passwd=" + yahoopassword + "&.save=Sign+In").Replace(" ", "").Replace("index", "");
         splitstring = splitstring.Substring(1, splitstring.Length - 1).Replace(":", "%3A").Replace("/", "%2F").Replace("knowsrch_ver=0&c=&ivt=&sg=", "knowsrch_ver%3D0%26c%3D%26ivt%3D%26sg%3D");
         string postdata = httphelper.Mainpost("https://login.yahoo.com/config/login?.done=http://answers.yahoo.com%2f&.src=knowsrch&.intl=us", splitstring);
     }
     catch (Exception ex)
     {
         MessageBox.Show(ex.ToString());
     }
 }