如何采用HTTP POST方式，给对方SP发送数据

Question

如何采用HTTP POST方式，给对方SP发送一个sequence_id=1234&service_num=22332211的数据呢

Answer 1

WebClient
<<.Net网络高级编程>> 这本书里面有讲.

Answer 2

byte[] response;WebClient webClient = new WebClient();
response = webClient.DownloadData(LOGIN_URL);string viewstate = ExtractViewState(
      Encoding.ASCII.GetString(response)
   );string postData = String.Format(
   "__VIEWSTATE={0}&UsernameTextBox={1}&PasswordTextBox={2}&LoginButton=Login",
   viewstate, USERNAME, PASSWORD);webClient.Headers.Add("Content-Type", "application/x-www-form-urlencoded");
response = webClient.UploadData(
        LOGIN_URL, "POST", Encoding.ASCII.GetBytes(postData)
    );
url here:
http://odetocode.com/Articles/162.aspx

Answer 3

or
private void Button5_Click(object sender, System.EventArgs e)
{
   // first, request the login form to get the viewstate value
   HttpWebRequest webRequest = WebRequest.Create(LOGIN_URL) as HttpWebRequest;         
   StreamReader responseReader = new StreamReader(
         webRequest.GetResponse().GetResponseStream()
      );
   string responseData = responseReader.ReadToEnd();         
   responseReader.Close();
   
   // extract the viewstate value and build out POST data
   string viewState = ExtractViewState(responseData);       
   string postData = 
         String.Format(
            "__VIEWSTATE={0}&UsernameTextBox={1}&PasswordTextBox={2}&LoginButton=Login",
            viewState, USERNAME, PASSWORD
         );
  
   // have a cookie container ready to receive the forms auth cookie
   CookieContainer cookies = new CookieContainer();   // now post to the login form
   webRequest = WebRequest.Create(LOGIN_URL) as HttpWebRequest;
   webRequest.Method = "POST";
   webRequest.ContentType = "application/x-www-form-urlencoded";
   webRequest.CookieContainer = cookies;        
   
   // write the form values into the request message
   StreamWriter requestWriter = new StreamWriter(webRequest.GetRequestStream());
   requestWriter.Write(postData);
   requestWriter.Close();
   
   // we don't need the contents of the response, just the cookie it issues
   webRequest.GetResponse().Close();
   
   // now we can send out cookie along with a request for the protected page
   webRequest = WebRequest.Create(SECRET_PAGE_URL) as HttpWebRequest;
   webRequest.CookieContainer = cookies;
   responseReader = new StreamReader(webRequest.GetResponse().GetResponseStream());
   
   // and read the response
   responseData = responseReader.ReadToEnd();
   responseReader.Close();
   
   Response.Write(responseData);         
}