public List <Speaker> ReadAllSpeakers(Filter filter)
{
if (filter.CurrentPage < 0 || filter.ItemsPrPage < 0)
{
throw new InvalidDataException("The entered paging is invalid");
}
if (((filter.CurrentPage - 1) * filter.ItemsPrPage) > _speakerRepository.Count())
{
throw new Exception("The current page you have selected is to high.");
}
return(_speakerRepository.ReadAllSpeakers(filter).ToList());
}