C# POST Form

public string HttpPostForm(string url,Dictionary<string,string> _form,string _filepath="")
{try{var formData = new MultipartFormDataContent();_form.Cast<KeyValuePair<string, string>>().ToList().ForEach(a =>{formData.Add(new StringContent(a.Key), a.Value);});if(_filepath.IsNotEmpty()){byte[] data = System.IO.File.ReadAllBytes(_filepath);formData.Add(new ByteArrayContent(data), "file", new FileInfo(_filepath).Name);}var result = new HttpClient().PostAsync(url, formData).Result.Content.ReadAsStringAsync().Result;Fmath.RunLog($"HttpPostForm:{url}\r\n{_form.ToJson()}\r\n{result}");return result;}catch (Exception Err){Fmath.RunLog($"HttpPostForm:{url}\r\n{_form.ToJson()}\r\n{Err.Message}");return "";}
}