public void Generate(string textWithId)
{
if (string.IsNullOrWhiteSpace(textWithId))
{
throw new ArgumentException("Empty text cannot be added.", "textWithId");
}
if (IsTextAdded(textWithId))
{
throw new ArgumentException(string.Format("Text '{0}' already added.", textWithId), "textWithId");
}
identifiedTexts.Add(Guid.NewGuid(), textWithId);
}