public void RemoveGrade(Predicate <Grade> p)
{
var gradeSatisfy = Grades.Where(p.Invoke).ToArray();
foreach (var grade in gradeSatisfy)
{
Grades.Remove(grade);
}
Save();
if (GradesChanged != null)
{
GradesChanged.Invoke();
}
}
public void EditGrade(Grade grade)
{
if (grade == null)
{
throw new ArgumentNullException();
}
foreach (var gradeInList in Grades.Where(gradeInList => gradeInList.Equals(grade)))
{
gradeInList.Mark = grade.Mark;
}
Save();
if (GradesChanged != null)
{
GradesChanged.Invoke();
}
}
public void AddGrade(Grade grade)
{
if (grade == null)
{
throw new ArgumentNullException();
}
//Method List<T>.Contains(T obj) uses the overriden Equals methods for objects Grade and Course, therefore it is eligible
if (Grades.Contains(grade))
{
throw new ArgumentException();
}
grade.Id = _idHolder++;
Grades.Add(grade);
Save();
if (GradesChanged != null)
{
GradesChanged.Invoke();
}
}