public void AddStudent(Student student)
{
if (student == null)
{
throw new ArgumentNullException("student", "Student cannot be null.");
}
if (this.students.Contains(student))
{
throw new InvalidOperationException("This student has been already added.");
}
if (student.GetType() != typeof(Student))
{
throw new ArgumentException("You cannot add non student objects to students");
}
if (this.students.Any(st => st.Id == student.Id))
{
throw new ArgumentException("There is already a student with the same ID.");
}
this.students.Add(student);
}
public void RemoveStudent(Student student)
{
if (student == null)
{
throw new ArgumentNullException("student", "Removing student requires student object as argument");
}
if (student.GetType() != typeof(Student))
{
throw new ArgumentException("You cannot remove non student objects from students");
}
if (!this.students.Contains(student))
{
throw new InvalidOperationException("There is no such student.");
}
this.students.Remove(student);
}