HTTP get、post请求

Post请求：

    string postData = "user=123&pass=456"; // 要发放的数据
    byte[] byteArray = Encoding.UTF8.GetBytes(postData);

    HttpWebRequest objWebRequest = (HttpWebRequest)WebRequest.Create("http://www.abc.com/a.aspx");
    objWebRequest.Method = "POST";
    objWebRequest.ContentType = "application/x-www-form-urlencoded";
    objWebRequest.ContentLength = byteArray.Length;
    Stream newStream = objWebRequest.GetRequestStream();
    // Send the data.
    newStream.Write(byteArray, , byteArray.Length); //写入参数
    newStream.Close();

    HttpWebResponse response = (HttpWebResponse)objWebRequest.GetResponse();
    StreamReader sr = new StreamReader(response.GetResponseStream(), Encoding.Default);
    string textResponse = sr.ReadToEnd(); // 返回的数据

接收参数：string a= Request.Form["user"];