IComparable / IEnumerable

gistfile1.txt

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Collections;


namespace ConsoleApplication15
{
    class Program
    {
        static void Main(string[] args)
        {
            Group group = new Group(0);

            group.addStudent(new Student("Sidor", "Sidorovitch", "Sidorov"));
            group.addStudent(new Student("Ivan", "Ivanovitch", "Ivanov"));
            group.addStudent(new Student("Semen", "Semenovith", "Semenov"));
            group.addStudent(new Student("Alexander", "Alexandrovitch", "Alexandrov"));           

            Console.WriteLine("-----------------------------------------------------");

            foreach (Student item in group)
            {
                Console.WriteLine(item.Name + " | " + item.FatherName + " | " + item.Surname);
            }

            Console.WriteLine("-----------------------------------------------------");

            Group.Print(group);

            Console.WriteLine("-----------------------------------------------------");

            group.Sort(new Student.SortByName());
            Group.Print(group);

            Console.WriteLine("-----------------------------------------------------");

            Student st = group.Search(new Group.SearchStudentByName("Alexander"));

            if (st != null)
            {
                Console.WriteLine(st.Name + " | " + st.FatherName + " | " + st.Surname);
            }

        }
    }

    public class ObjectIsNotStudent : Exception
    {
        public ObjectIsNotStudent() : base() { }
    }

    public interface IStudentSearcher
    {
        void SetStudents(Student[] students);

        Student Search();
    }

    public class Student : IComparable
    {
        private String name;

        private String fatherName;

        private String surname;

        private DateTime birthday;

        private String address;

        private String phoneNumber;

        private static int courseWorkCount = 5;

        private static int creditCount = 5;

        private static int examCount = 5;

        private int[] courseWorkMarks = new int[courseWorkCount];

        private int[] creditMarks = new int[creditCount];

        private int[] examMarks = new int[examCount];

        public int CompareTo(Object obj)
        {
            Student temp = obj as Student;

            if (temp == null)
            {
                throw new ObjectIsNotStudent();
            }

            int diff = 0;

            diff = Birthday.Year - temp.Birthday.Year;

            if (diff != 0)
                return diff;

            diff = Birthday.Month - temp.Birthday.Month;

            if (diff != 0)
                return diff;

            diff = Birthday.Day - temp.Birthday.Day;

            return diff;
        }

        public class SortByName : IComparer
        {
            public int Compare(Object obj1, Object obj2)
            {
                Student s1 = obj1 as Student;
                Student s2 = obj2 as Student;

                if (s1 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                if (s2 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                return String.Compare(s1.Name, s2.Name);
            }
        }

        public class SortBySurname : IComparer
        {
            public int Compare(Object obj1, Object obj2)
            {
                Student s1 = obj1 as Student;
                Student s2 = obj2 as Student;

                if (s1 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                if (s2 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                return String.Compare(s1.Surname, s2.Surname);
            }
        }

        public class SortByFatherName : IComparer
        {
            public int Compare(Object obj1, Object obj2)
            {
                Student s1 = obj1 as Student;
                Student s2 = obj2 as Student;

                if (s1 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                if (s2 == null)
                {
                    throw new ObjectIsNotStudent();
                }

                return String.Compare(s1.FatherName, s2.FatherName);
            }
        }

        public String Name
        {
            get
            {
                return name;
            }
            set
            {
                setName(value);
            }
        }

        public String FatherName
        {
            get
            {
                return fatherName;
            }
            set
            {
                setFatherName(value);
            }
        }

        public String Surname
        {
            get
            {
                return surname;
            }
            set
            {
                setSurname(value);
            }
        }

        public DateTime Birthday
        {
            get
            {
                return getBirthday();
            }
            set
            {
                setBirthday(value);
            }
        }

        public String Address
        {
            get { return getAddress(); }
            set { setAddress(value); }
        }

        public String Phone
        {
            get { return getPhoneNumber(); }
            set { setPhoneNumber(value); }
        }

        public Student(String name, String fatherName, String surname,
                        DateTime birthday, String address, String phoneNumber)
        {
            setName(name);
            setFatherName(fatherName);
            setSurname(surname);
            setBirthday(birthday);
            setAddress(address);
            setPhoneNumber(phoneNumber);

            fillDefaultMarkValues();
        }

        public Student() : this("Unknown", "Unknown", "Unknown", new DateTime(1900, 1, 1), "", "") { }

        public Student(String name, String fatherName, String surname) :
            this(name, fatherName, surname, new DateTime(1900, 1, 1), "", "")
        { }

        public void setName(String name)
        {
            this.name = name;
        }

        public void setFatherName(String fatherName)
        {
            this.fatherName = fatherName;
        }

        public void setSurname(String surname)
        {
            this.surname = surname;
        }

        public void setBirthday(DateTime birthday)
        {
            this.birthday = birthday;
        }

        public void setAddress(String address)
        {
            this.address = address;
        }

        public void setPhoneNumber(String phoneNumber)
        {
            this.phoneNumber = phoneNumber;
        }

        public void setCourseWorkMark(int mark, int index)
        {
            if ((index > courseWorkCount - 1) || (index < 0))
            {
                return;//an exception should be here
            }

            courseWorkMarks[index] = mark;
        }

        public void setCreditkMark(int mark, int index)
        {
            if ((index > creditCount - 1) || (index < 0))
            {
                return;//an exception should be here
            }

            creditMarks[index] = mark;
        }

        public void setExamMark(int mark, int index)
        {
            if ((index > examCount - 1) || (index < 0))
            {
                return;//an exception should be here
            }

            examMarks[index] = mark;
        }

        public String getName()
        {
            return name;
        }

        public String getFatherName()
        {
            return fatherName;
        }

        public String getSurname()
        {
            return surname;
        }

        public DateTime getBirthday()
        {
            return birthday;
        }

        public String getAddress()
        {
            return address;
        }

        public String getPhoneNumber()
        {
            return phoneNumber;
        }

        public int getCourseWorkMark(int index)
        {
            if ((index > courseWorkCount - 1) || (index < 0))
            {
                return 0;//an exception should be here
            }

            return courseWorkMarks[index];
        }

        public int getCreditMark(int index)
        {
            if ((index > examCount - 1) || (index < 0))
            {
                return 0;//an exception should be here
            }

            return examMarks[index];
        }

        public int getExamMark(int index)
        {
            if ((index > examCount - 1) || (index < 0))
            {
                return 0;//an exception should be here
            }

            return examMarks[index];
        }

        public void showStudentInfo()
        {
            Console.WriteLine("Name: " + name);
            Console.WriteLine("Father name: " + fatherName);
            Console.WriteLine("Surname: " + surname);
            Console.WriteLine("Birthday: " + birthday.ToString());
            Console.WriteLine("Address: " + address);
            Console.WriteLine("Phone number: " + phoneNumber);

            showMarks();
        }

        public int calculateAvarageMark()
        {
            int summMark = 0;
            int divider = 0;

            calculateCreditMarkSumm(ref summMark, ref divider);
            calculateCourseWorkMarkSumm(ref summMark, ref divider);
            calculateExamMarkSumm(ref summMark, ref divider);

            if (divider == 0)
                return 0;
            else
                return summMark / divider;
        }

        public void fillCreditMarkArrayWithMark(int mark)
        {
            for (int i = 0; i < creditMarks.Length; i++)
            {
                setCreditkMark(mark, i);
            }
        }

        public void fillCourseWorkMarkArrayWithMark(int mark)
        {
            for (int i = 0; i < courseWorkMarks.Length; i++)
            {
                setCourseWorkMark(mark, i);
            }
        }

        public void fillExamMarkArrayWithMark(int mark)
        {
            for (int i = 0; i < examMarks.Length; i++)
            {
                setExamMark(mark, i);
            }
        }

        private void calculateCreditMarkSumm(ref int summMark, ref int divider)
        {
            divider++;

            for (int i = 0; i < creditMarks.Length; i++)
            {
                summMark += creditMarks[i];
            }

        }

        private void calculateCourseWorkMarkSumm(ref int summMark, ref int divider)
        {
            divider++;

            for (int i = 0; i < courseWorkMarks.Length; i++)
            {
                summMark += courseWorkMarks[i];
            }
        }

        private void calculateExamMarkSumm(ref int summMark, ref int divider)
        {
            divider++;

            for (int i = 0; i < examMarks.Length; i++)
            {
                summMark += examMarks[i];
            }
        }

        private void showMarks()
        {
            showCourseWorkMarks();
            showCreditkMarks();
            showExamMarks();
        }

        private void showCourseWorkMarks()
        {
            Console.Write("Couse work marks: ");

            for (int i = 0; i < courseWorkMarks.Length; i++)
            {
                Console.Write("{0, 4}", courseWorkMarks[i]);
            }

            Console.WriteLine();
        }

        private void showCreditkMarks()
        {
            Console.Write("Credit marks: ");

            for (int i = 0; i < creditMarks.Length; i++)
            {
                Console.Write("{0, 4}", creditMarks[i]);
            }

            Console.WriteLine();

        }

        private void showExamMarks()
        {
            Console.Write("Exam marks: ");

            for (int i = 0; i < examMarks.Length; i++)
            {
                Console.Write("{0, 4}", examMarks[i]);
            }

            Console.WriteLine();

        }

        private void fillDefaultMarkValues()
        {

            fillArrayWithZero(courseWorkMarks);
            fillArrayWithZero(creditMarks);
            fillArrayWithZero(examMarks);
        }

        private void fillArrayWithZero(int[] markArray)
        {

            for (int i = 0; i < markArray.Length; i++)
                markArray[i] = 0;
        }
    }

    //public class SurnameCompare : IComparer
    //{
    //    public int Compare(object a, object b)
    //    {
    //        Student studentA = (Student)a;
    //        Student studentB = (Student)b;
    //        return studentA.getSurname().CompareTo(studentB.getSurname());
    //    }
    //}

    public class Group : IEnumerable
    {
        private Student[] students;

        private int studentCount;

        private String groupName;

        private String groupSpecialization;

        private int courseNumber;

        public int StudentCount
        {
            get { return getStudnetCount(); }
            set { setStudentCount(value); }
        }

        public String GroupName
        {
            get
            {
                return getGroupName();
            }
            set
            {
                setGroupName(value);
            }
        }

        public String GroupSpecialization
        {
            get
            {
                return getGroupSpecialization();
            }
            set
            {
                setGroupSpecialization(value);
            }
        }

        public int CourseNumber
        {
            get
            {
                return getCourseNumber();
            }
            set
            {
                setCourseNumber(value);
            }
        }

        public class SearchStudentByName : IStudentSearcher
        {
            private Student[] students;

            private String name;

            public SearchStudentByName(String name)
            {
                this.name = name;
            }

            public Student Search()
            {
                if (students == null)
                {
                    return null;
                }

                foreach (Student item in students)
                {
                    if (item.Name.Equals(name))
                    {
                        return item;
                    }
                }

                return null;
            }

            public void SetStudents(Student[] students)
            {
                this.students = students;
            }
        }

        public class SearchStudentBySurname : IStudentSearcher
        {
            private Student[] students;

            private String surname;

            public SearchStudentBySurname(String surname)
            {
                this.surname = surname;
            }

            public Student Search()
            {
                if (students == null)
                {
                    return null;
                }

                foreach (Student item in students)
                {
                    if (item.Surname.Equals(surname))
                    {
                        return item;
                    }
                }

                return null;
            }

            public void SetStudents(Student[] students)
            {
                this.students = students;
            }
        }

        public Student Search(IStudentSearcher criteria)
        {
            criteria.SetStudents(students);
            return criteria.Search();
        }

        public void Sort(IComparer criteria)
        {
            Array.Sort(students, criteria);
        }

        public static void Print(Group group)
        {
            foreach (Student item in group)
            {
                Console.WriteLine(item.Name + " | " + item.FatherName + " | " + item.Surname);
            }
        }

        IEnumerator IEnumerable.GetEnumerator()
        {
            return (IEnumerator)GetEnumerator();
        }

        public GroupEum GetEnumerator()
        {
            return new GroupEum(students);
        }

        public void addStudent(Student new_student)
        {
            Student[] prev_students = this.students;
            students = new Student[studentCount + 1];

            if (prev_students != null)
            {
                for (int i = 0; i < prev_students.Length; i++)
                {
                    students[i] = prev_students[i];
                }
            }

            students[studentCount] = new_student;

            studentCount++;

            sortStudentsBySurname();
        }

        public Student getStudentByIndex(int index)
        {
            if (index < 0 || index > students.Length - 1)
                return null;//must be exception;
            else
                return students[index];
        }

        public void deleteStudentByIndex(int index)
        {
            if (index < 0 || index > students.Length - 1)
                return;//must be exception;

            Student[] prev_students = this.students;
            students = new Student[studentCount - 1];
            int shift = 0;

            for (int i = 0; i < prev_students.Length; i++)
            {
                if (i == index)
                {
                    shift++;
                    continue;
                }

                students[i - shift] = prev_students[i];
            }

            studentCount--;

            sortStudentsBySurname();
        }

        public void setStudentCount(int studentCount)
        {
            this.studentCount = studentCount;
        }

        public int getStudnetCount()
        {
            return studentCount;
        }

        public void setGroupName(String groupName)
        {
            this.groupName = groupName;
        }

        public String getGroupName()
        {
            return groupName;
        }

        public void setGroupSpecialization(String groupSpecialization)
        {
            this.groupSpecialization = groupSpecialization;
        }

        public String getGroupSpecialization()
        {
            return groupSpecialization;
        }

        public void setCourseNumber(int courseNumber)
        {
            this.courseNumber = courseNumber;
        }

        public int getCourseNumber()
        {
            return courseNumber;
        }

        public void showGroup()
        {
            Console.WriteLine("Group name: " + groupName);
            Console.WriteLine("Group spesialization: " + groupSpecialization);
            Console.WriteLine("Course number: " + courseNumber.ToString());
            Console.WriteLine("Student count: " + studentCount.ToString());
            Console.WriteLine("----------------------------------------");

            for (int i = 0; i < students.Length; i++)
            {
                Console.WriteLine((i + 1).ToString() + ". " + students[i].getSurname() + " " + students[i].getName() +
                                    " " + students[i].getFatherName() + ", " + students[i].calculateAvarageMark().ToString());
            }

        }

        public Group()
        {
            fillGroupAttributesWithDefaultValues();
            addStudentAutomaticaly(10);
        }

        public Group(int studentCount)
        {
            fillGroupAttributesWithDefaultValues();
            addStudentAutomaticaly(studentCount);
        }

        public Group(Student[] students)
        {
            fillGroupAttributesWithDefaultValues();

            foreach (var item in students)
            {
                addStudent(item);
            }
        }

        public Group(String groupName, String groupSpecialization, int courseNumber)
        {
            setGroupName(groupName);
            setGroupSpecialization(groupSpecialization);
            setCourseNumber(courseNumber);
        }

        public void deleteStudentWithLowestMark()
        {
            if (studentCount == 0)
            {
                return;
            }

            int index = 0;
            int lowestMark = 1000;

            for (int i = 0; i < students.Length; i++)
            {
                if (students[i].calculateAvarageMark() < lowestMark)
                {
                    lowestMark = students[i].calculateAvarageMark();
                    index = i;
                }
            }

            deleteStudentByIndex(index);
        }

        public void setStudentData(int studentIndex, String name, String fatherName, String surname)
        {
            Student currentStudent = getStudentByIndex(studentIndex);
            currentStudent.setName(name);
            currentStudent.setFatherName(fatherName);
            currentStudent.setSurname(surname);

            sortStudentsBySurname();
        }

        public void moveStudentToAnotherGroup(int studentIndex, Group newGroup)
        {
            newGroup.addStudent(getStudentByIndex(studentIndex));
            deleteStudentByIndex(studentIndex);
        }

        private void fillGroupAttributesWithDefaultValues()
        {
            setGroupName("Unknown");
            setGroupSpecialization("Unknown");
            setCourseNumber(0);
        }

        private void addStudentAutomaticaly(int count)
        {
            for (int i = 0; i < count; i++)
            {
                Student newStudent = new Student("Unknown" + i.ToString(), "Unknown" + i.ToString(), "Unknown" + i.ToString());
                newStudent.fillCourseWorkMarkArrayWithMark(i + 1);
                newStudent.fillCreditMarkArrayWithMark(i + 1);
                newStudent.fillExamMarkArrayWithMark(i + 1);
                addStudent(newStudent);
            }
        }

        private void sortStudentsBySurname()
        {
            //IComparer comparer = new SurnameCompare();
            //Array.Sort(students, comparer);
        }
    }

    public class GroupEum : IEnumerator
    {
        public Student[] _students;

        int position = -1;

        public GroupEum(Student[] list)
        {
            _students = list;
        }

        public bool MoveNext()
        {
            position++;
            return (position < _students.Length);
        }

        public void Reset()
        {
            position = -1;
        }

        object IEnumerator.Current
        {
            get
            {
                return Current;
            }
        }

        public Student Current
        {
            get
            {
                try
                {
                    return _students[position];
                }
                catch (IndexOutOfRangeException)
                {
                    throw new InvalidOperationException();
                }
            }
        }
    }
}