private void button1_Click(object sender, EventArgs e)
        {

            string requestmethod = "POST";
            string postData = "username=testmember&pwd=web123";
            //The Byte Array that will be used for writing the data to the stream.
            byte[] byteArray = Encoding.UTF8.GetBytes(postData);

            //The URL of the webpage to send the data to.
            string URL = "http://marketplace.plastopedia.com/login.php";

            //The type of content being send, this is almost always "application/x-www-form-urlencoded".
            string contenttype = "application/x-www-form-urlencoded";

            //What the server sends back:
            string responseFromServer = null;
            WebRequest request = WebRequest.Create(URL);

            //We also need a Stream:
            Stream dataStream;

            //...And a webResponce,
            WebResponse response;

            //don't forget the streamreader either!
            StreamReader reader; //We will need to set the method used to send the data.
            request.Method = requestmethod;

            //Then the contenttype:
            request.ContentType = contenttype;

            //content length
            request.ContentLength = byteArray.Length;

            //ok, now get the request from the webRequest object, and put it into our Stream:
            dataStream = request.GetRequestStream();

            // Write the data to the request stream.
            dataStream.Write(byteArray, 0, byteArray.Length);

            // Close the Stream object.
            dataStream.Close();
            response = request.GetResponse();

            // Get the stream containing content returned by the server.
            dataStream = response.GetResponseStream();

            //Open the responce stream:
            reader = new StreamReader(dataStream);

            //read the content into the responcefromserver string
            responseFromServer = reader.ReadToEnd();

            // Clean up the streams.
            reader.Close();
            dataStream.Close();
            response.Close();


            //Now, display the responce!
            Console.WriteLine(responseFromServer);