help

i try a lot of times but dont succeed..
where am i did mistake?

using System;
using System.IO;
using System.Net;
using System.Text;

namespace Examples.System.Net
{
public class WebRequestPostExample
{
public static void Main()
{
// Create a request using a URL that can receive a post.
WebRequest request = WebRequest.Create(“https://www.hackthis.co.uk/levels/intermediate/2”);
// Set the Method property of the request to POST.
request.Method = “POST”;
// Create POST data and convert it to a byte array.
string postData = “”;
byte[] byteArray = Encoding.UTF8.GetBytes(postData);
// Set the ContentType property of the WebRequest.
request.ContentType = “application/x-www-form-urlencoded”;
// Set the ContentLength property of the WebRequest.
request.ContentLength = byteArray.Length;
// Get the request stream.
Stream dataStream = request.GetRequestStream();
// Write the data to the request stream.
dataStream.Write(byteArray, 0, byteArray.Length);
// Close the Stream object.
dataStream.Close();
// Get the response.
WebResponse response = request.GetResponse();
// Display the status.
Console.WriteLine(((HttpWebResponse)response).StatusDescription);
// Get the stream containing content returned by the server.
dataStream = response.GetResponseStream();
// Open the stream using a StreamReader for easy access.
StreamReader reader = new StreamReader(dataStream);
// Read the content.
string responseFromServer = reader.ReadToEnd();
// Display the content.
Console.WriteLine(responseFromServer);
// Clean up the streams.
reader.Close();
dataStream.Close();
response.Close();

    }  
}  

}