public void AddnSetCurrent(string name)
{
if (string.IsNullOrWhiteSpace(name))
{
throw new ArgumentNullException("Имя не может быть пустым или null");
}
Phones = GetPhones();
current_phone = Phones.SingleOrDefault(x => x.Name == name);
if (current_phone == null)
{
current_phone = new Phone(name);
Phones.Add(current_phone);
newPhone = true;
Save();
}
}