Chương 5-Bài 11. Làm quen Hướng đối tượng trong C#

Mô tả bài toán

• Create a new project, and include in it the class Person that you just created.
• Create a class "Student" and another class "Teacher", both descendants of "Person".
• The class "Student" will have a public method "GoToClasses", which will write on screen "I’m going to class."
• The class "Teacher" will have a public method "Explain", which will show on screen "Explanation begins". Also, it will have a private attribute "subject", a string.
• The class Person must have a method "SetAge (int n)" which will indicate the value of their age (eg, 20 years old).
• The student will have a public method "ShowAge" which will write on the screen "My age is: 20 years old" (or the corresponding number).
• You must create another test class called "StudentAndTeacherTest" that will contain "Main" and:
  • Create a Person and make it say hello
  • Create a student, set his age to 21, tell him to Greet and display his age
  • Create a teacher, 30 years old, ask him to say hello and then explain.

Cách giải quyết

• Class Person, có:
  • Thuộc tính (property):
    • Age: tuổi
  • Phương thức (method):
    • Greet: hiển thị câu chào mừng "Hello"
    • SetAge: gán giá trị cho thuộc tính tuổi Age
• Class Student kế thừa từ class Person, có thêm:
  • Phương thức (method):
    • ShowAge: hiển thị thông tin tuổi.
• Class Teacher kế thừa từ class Person, có thêm:
  • Thuộc tính (property):
    • subject: môn giảng dạy
  • Phương thức (method):
    • Explain: giảng bài cho Sinh viên

Source code

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

namespace TeacherAndStudentOOP
{
    class Person
    {
        protected int age;

        public void Greet()
        {
            Console.WriteLine("Hello");
        }

        public void SetAge(int n)
        {
            age = n;
        }
    }

    class Student : Person
    {
        public void ShowAge()
        {
            Console.WriteLine("My age is: {0} years old", age);
        }
    }

    class Teacher : Person
    {
        private string subject;

        public void Explain()
        {
            Console.WriteLine("Explanation begins");
        }
    }

    class StudentAndTeacherTest
    {
        static void Main()
        {
            bool debug = false;

            Person myPerson = new Person();
            myPerson.Greet();

            Student myStudent = new Student();
            myStudent.SetAge(21);
            myStudent.Greet();
            myStudent.ShowAge();

            Teacher myTeacher = new Teacher();
            myTeacher.SetAge(30);
            myTeacher.Greet();
            myTeacher.Explain();

            if (debug)
                Console.ReadLine();
            Console.ReadKey();
        }
    }
}

Github