在c#中使用catchom

我想在c#中使用catchom，但无法找到任何示例如果有的话，请提供一些示例代码。

我有这个curl的样品

谁能把这个转换成c#

 curl -F "image=@CATask1-Correct.png" -F "token=sometoken" https://r.catchoom.com/v1/search

我试着像这样转换

string url = "https://r.catchoom.com/v1/search";

       WebRequest myReq = WebRequest.Create(url);
       myReq.Headers["token"] = "sometoken";
       myReq.Headers["image"] = "imageurl";
       string username = "someid";
       string password = "pwd";
       string usernamePassword = username + ":" + password;
       CredentialCache mycache = new CredentialCache();
       mycache.Add(new Uri(url), "Basic", new NetworkCredential(username, password));
       myReq.Credentials = mycache;
       myReq.Headers.Add("Authorization", "Basic " + Convert.ToBase64String(new ASCIIEncoding().GetBytes(usernamePassword)));
       WebResponse wr = myReq.GetResponse();
       Stream receiveStream = wr.GetResponseStream();
       StreamReader reader = new StreamReader(receiveStream, Encoding.UTF8);
       string content = reader.ReadToEnd();

但是抛出错误，404没有找到

谢谢