public static async Task<TwitterSuccess> AddUsersToList(this IUserSession session, long listId, string slug,
IEnumerable<string> screenNames, IEnumerable<long> userIds,
string ownerScreenName = "", long ownerId = 0)
{
var parameters = new TwitterParametersCollection();
parameters.Create(list_id: listId, slug: slug, owner_id: ownerId, owner_screen_name: ownerScreenName);
parameters.CreateCollection(screen_names:screenNames,user_ids:userIds);
if (parameters.EnsureEitherOr("screen_name", "user_id").IsFalse())
{
return session.MapParameterError<TwitterSuccess>(
"Either screen_names or user_ids required");
}
return await session.PostAsync(TwitterApi.Resolve("/1.1/lists/members/create_all.json"), parameters)
.ContinueWith(c => c.MapToTwitterSuccess());
}