Visual Studio 2012 中的 HTTPClient POST

Question

我想将数据发布到 REST API，但它没有创建正确的请求：using (var client = new HttpClient()){client.DefaultRequestHeaders.Add("Accept", "text/csv");HttpResponseMessage response = null;string baseUrl = ServiceUrl + "/api/v25/upload/test";Dictionary<string, string> parameters = new Dictionary<string, string>();parameters.Add("field1", "value1");parameters.Add("field2", "value2");MultipartFormDataContent form = new MultipartFormDataContent();HttpContent content = new StringContent("long text...");content.Headers.ContentType = new MediaTypeHeaderValue("text/csv");HttpContent fields = new FormUrlEncodedContent(parameters);form.Add(content, "message");form.Add(fields);response = client.PostAsync(baseUrl, form).Result;var message = response.Content.ReadAsStringAsync().Result;}它使这个 URL：POST /api/v25/upload/test HTTP/1.1这将是正确的地址：POST /api/v25/upload/test?field1=value1&field2=value2 HTTP/1.1请问代码错误在哪里？