Tài liệu Thực hành thừa kế doc

namespace Thuc_Hanh_Thua_Ke { public class HinhVuong : Hinh { private double chieuDaiCanh = 1; public double ChieuDaiCanh { get { return chieuDaiCanh; } set { if (value > 0) { chieuDaiCanh = value; } } } public HinhVuong() : base(4) { } public HinhVuong(double a) : base(4) { chieuDaiCanh = a; } //cac ham thua ke public override void NhapHinh() { //Console.WriteLine("Nhap chieu dai canh hinh vuong{0}", chieuDaiCanh); //sua lai Console.WriteLine("Nhap chieu dai canh hinh vuong"); chieuDaiCanh = double.Parse(Console.ReadLine()); } public override void InHinh() { //in theo mau cua de bai Console.WriteLine("Hinh vuong:"); Console.WriteLine("Canh = {0}", chieuDaiCanh); Console.WriteLine("Chu vi = {0}", this.ChuVi()); Console.WriteLine("Dien tich = {0}", this.DienTich()); } public override double ChuVi() { double kq = 0; kq = ChieuDaiCanh * 4; return kq; } public override double DienTich() { double kq = 0; kq = ChieuDaiCanh * ChieuDaiCanh; return kq; } } } namespace Thuc_Hanh_Thua_Ke { public class HinhChuNhat : Hinh { private double chieuDaiCanhA = 1; public double ChieuDaiCanhA { get { return chieuDaiCanhA; } set { chieuDaiCanhA = value; } } private double chieuDaiCanhB = 1; public double ChieuDaiCanhB { get { return chieuDaiCanhB; } set { chieuDaiCanhB = value; } } public HinhChuNhat() : base(4) { chieuDaiCanhA = 1; chieuDaiCanhB = 1; } public HinhChuNhat(double a, double b) :base(4) { chieuDaiCanhA = 1; chieuDaiCanhB = 1; } //cac ham thua ke public override void NhapHinh() { Console.WriteLine("Nhap chieu dai canh hinh chu nhat"); chieuDaiCanhA = double.Parse(Console.ReadLine()); Console.WriteLine("Nhap chieu rong canh hinh chu nhat"); chieuDaiCanhB = double.Parse(Console.ReadLine()); } public override void InHinh() { //in thao mau cua de bai Console.WriteLine("Hinh chu nhat"); Console.WriteLine("Canh ngan = {0}", chieuDaiCanhA); Console.WriteLine("Canh dai = {0}", chieuDaiCanhB); Console.WriteLine("Chu vi = {0}", this.ChuVi()); Console.WriteLine("Dien tich = {0}", this.DienTich()); } public override double ChuVi() { double kq = 0; kq = (ChieuDaiCanhA + ChieuDaiCanhB) * 2; return kq; } public override double DienTich() { double kq = 0; kq = ChieuDaiCanhA * ChieuDaiCanhB; return kq; } } }