post form data error

[teamy]

i am trying to develop an app. that will send form datas to web pages. when I write following expression to browser's adress line it accepts user name and password then redirects me to date.asp.

ex.

http://xxx.webpage.com/login.asp?txtUser=userName&txtPass=passWord&cmdOK=Submit

Then I try to use that expression as follows but when I read the response stream, i see that it is still the login.asp page (not date.asp).

WebRequest wrq = WebRequest.Create("

http://xxx.webpage.com/login.asp?txtUser=userName&txtPass=passWord&cmdOK=Submit");

WebResponse response = wrq.GetResponse();
Stream responseStream = response.GetResponseStream();
StreamReader reader = new StreamReader (responseStream);
String res = reader.ReadToEnd ();
textBox1.Text = res;

I also tried to POST data via outputstream as follows:

ASCIIEncoding encoding=new ASCIIEncoding();
string postData= "txtUser=jfa&txtPass=jfa&cmdOK=Submit"
byte[] data = encoding.GetBytes(postData);

string address = "

http://xxx.webpage.com/login.asp";

WebRequest wrq = WebRequest.Create(address);
wrq.Method = "POST";
wrq.ContentType = "application/x-

http://www-form-urlencoded";

wrq.ContentLength = data.Length;

Stream outputStream = wrq.GetRequestStream();
outputStream.Write (data, 0, data.Length);
outputStream.Close ();

//read response

WebResponse response = wrq.GetResponse();
Stream responseStream = response.GetResponseStream();
StreamReader reader = new StreamReader (responseStream);
String res = reader.ReadToEnd ();
textBox1.Text = res;

but it didn't work again.. Waiting for any idea. thanks