title: C# HTTP post , how to post with List<XX> parameter?
body: <pre><code>using (WebClient wc = new WebClient())
  {
      wc.Headers[HttpRequestHeader.ContentType] = "application/x-www-form-urlencoded";
      string HtmlResult = wc.UploadString(url, "sign=fsadfasdf&amp;charset=utf-8");
  }
  </code></pre>
  
  <p>Server can get value of sign and charset.</p>
  
  <p>But there is a third parameter LIST, which is a list of object (this object is an entity class).
  How can I pass this parameter to the server?</p>
  
  <p>I tried to use <code>"sign=fsadfasdf&amp;charset=hhh&amp;list=" + Json(list)</code> as postData (convert List to json string).  But the server didn't get value of this list param.</p>