HTTP Post Though C#

using(WebClient client = new WebClient()) {
    string responseString = client.UploadString(address, requestString);
}

HttpWebRequest request= (HttpWebRequest)WebRequest.Create(url);
request.ContentType="application/x-www-form-urlencoded";
request.Method = "POST";
request.KeepAlive = true;

using (Stream requestStream = request.GetRequestStream())
{
    requestStream.Write(BytePost,0,BytePost.Length);
    requestStream.Close();
}

HttpWebResponse response = (HttpWebResponse)request.GetResponse();
using(StreamReader sr = new StreamReader(response.GetResponseStream()))
{
    responseString = sr.ReadToEnd();
}