.net中具有附加參數的Multipart / form-data

Question

在.net中創建這樣的發布請求的最佳方法是什么？ 我嘗試使用HttpClient和MultipartFormDataContent類，但到目前為止，我只能上傳圖像。 如何添加其他參數，例如api鍵？

  POST /services/upload/ HTTP/1.1
    Content-Type: multipart/form-data; boundary=---------------------------7d44e178b0434
    Host: api.flickr.com
    Content-Length: 35261

    -----------------------------7d44e178b0434
    Content-Disposition: form-data; name="api_key"

    3632623532453245
    -----------------------------7d44e178b0434
    Content-Disposition: form-data; name="auth_token"

    436436545
    -----------------------------7d44e178b0434
    Content-Disposition: form-data; name="api_sig"

    43732850932746573245
    -----------------------------7d44e178b0434
    Content-Disposition: form-data; name="photo"; filename="C:\test.jpg"
    Content-Type: image/jpeg

    {RAW JFIF DATA}
    -----------------------------7d44e178b0434--

Answer 1

在C＃+ .NET 4.0中...

Uri uri =  new Uri("api.flickr.com");
HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
request.Method = "POST";

//goes into the body. not header
NameValueCollection queryString = HttpUtility.ParseQueryString(string.Empty);
queryString["api_key"] = "7d44e178b0434";
...

object returnValue = null;
 try
            {
                using (var writer = new StreamWriter(request.GetRequestStream()))
                {
                    writer.WriteLine(queryString);
                }

                returnValue = request.GetResponse();
            }
            catch (Exception ex)
            {
               ..
            }

如果您想在標題中添加一些內容，

 request.Headers.Add("HeaderKEY", somevalue);