static void ChangeKey(string key)
{
DocumentProgram documentProgram;
switch (key)
{
case "basic":
documentProgram = new DocumentProgram();
break;
case "pro":
documentProgram = new ProDocumentProgram();
break;
case "expert ":
documentProgram = new ExpertDocument();
break;
default:
throw new ArgumentException("Keyword is not valid");
}
ShowFull(documentProgram);
}
static void ShowFull(DocumentProgram documentProgram)
{
documentProgram.OpenDocument();
documentProgram.EditDocument();
documentProgram.SaveDocument();
}