public void Active()
{
ClassRoom Classes = new ClassRoom();
char askToContinue;
var enterChoice = new EnterInformation();
var interFace = new InterfaceOfUser();
int optionItem;
int isStudentExist;
string userInput;
do
{
interFace.MainMenu();
do
{
userInput = enterChoice.EnterUserInput();
optionItem = interFace.CheckAndReturn(userInput);
} while (optionItem == -1);
switch (optionItem)
{
case 1:
Console.Clear();
Classes.GetInformationOfGroup();
break;
case 2:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist != 0)
{
Classes.FuntionCheckInformation();
break;
}
else
{
break;
}
case 3:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist == 0)
{
break;
}
else
{
Classes.FindByID();
}
break;
case 4:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist == 0)
{
break;
}
else
{
Classes.FindStudentsHaveHighestAverageGrade();
}
break;
case 5:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist == 0)
{
break;
}
else
{
Classes.FindFailGrade();
}
break;
case 6:
Console.Clear();
Classes.GetInformationASingleStudent();
break;
case 7:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist == 0)
{
break;
}
else
{
Classes.CalculateAverages();
}
break;
case 8:
Console.Clear();
isStudentExist = interFace.CheckStudentExist(Classes.Students.Count);
if (isStudentExist == 0)
{
break;
}
else
{
Classes.DeleteStudentById();
}
break;
case 0: Console.Clear(); Console.Write("DONE"); break;
default: Console.Clear(); Console.WriteLine("ERROR"); break;
}
askToContinue = interFace.CheckToContinue(optionItem);
} while (optionItem != 0 && askToContinue == 'y');
}