public string AllValuesAsString()
{
string participants = string.Join(",", (Participants?.Select(x => string.Concat(x.Key.ToString(), String.Join("|", x.Value?.Select(v => v.AllValuesAsString()).ToList() ?? new List <string>()))).ToList() ?? new List <string>()));
string rejected = string.Join(",", (Rejected?.Select(x => x.UsernameOrName()).ToList() ?? new List <string>()));
string maybe = string.Join(",", (Maybe?.Select(x => x.UsernameOrName()).ToList() ?? new List <string>()));
string done = string.Join(",", (Done?.Select(x => x.UsernameOrName()).ToList() ?? new List <string>()));
return($"{UniqueID};{PublicID};{Raid?.AllValuesAsString()};{participants};{rejected};{done};{maybe};{IsPublished};{LastModificationTime}");
}