Link Video Bài Giảng

Nội dung chính trong buổi học:
- delegate + event + collections (List, ArrayList, Dictionary (Hashmap), Stack, Queue)

Bài toán:
Viết 1 chương trình phần mềm quản lý bán hàng cho siêu thì VinMart

Một số chức năng trong dự án
- Quản lý KH
- Quản lý danh mục
- Quản lý thương hiệu (Brand)
- Quản lý sản phẩm
- Quản lý promotion
- Quản lý đơn hàng
- Quản lý phản hồi
...

Senior & SA: Lên cấu trúc của dự án.

Modules -> Ứng dụng khá nhiều trong projects

- Database
- Hàm sẽ đc sử dụng lại cho cả project, .v.v

Projects:
	Entities (Mapping tables <-> class objects) -> GEN tự động
	Database -> Có sẵn trọng Framework
		Config -> database
		DBHelper
	Utils
		Utility -> rất nhiều loại khác nhau -> Sử dụng trong cả project
	Modules
		Customer
			-
			-
			-
		Category
		Brand
		Product
		Order
		Promotion
		Feedback

Exception:
	Thiết kế lớp đối tượng Student -> Fullname, Age, Email -> Hàm tạo đẩy đủ các tham số đầu vào
	Age >= 0
	Email chữa ký tự @

	Age < 0 -> AgeException
	Email @ -> EmailException

	Test -> Chương trình hàm tạo -> Bắt lỗi cho 2 exception trên -> Hiển thị message phù hợp cho từng TH

Interface & Abtract class -> Ko khoi tao dc object truc tiep tu interface & abstract
Anonymous class -> interface & abstract

Ví dụ tạo khung dự án:

Exception

#Student.cs

using System;
namespace Lesson05.Exceptions
{
    public class Student
    {
        public string Fullname { get; set; }
        public int Age { get; set; }
        public string Email { get; set; }

        public Student()
        {
        }

        public Student(string fullname, int age, string email)
        {
            if(age < 0)
            {
                throw new AgeException();
                //throw new Exception("Age exception");
            }
            if(!email.Contains("@")) {
                throw new EmailException();
                //throw new Exception("Email exception");
            }

            Fullname = fullname;
            Age = age;
            Email = email;
        }
    }
}

#EmailException.cs

using System;
namespace Lesson05.Exceptions
{
    public class EmailException : Exception
    {
        public EmailException()
        {
        }
    }
}

#AgeException.cs

using System;
namespace Lesson05.Exceptions
{
    public class AgeException : Exception
    {
        public AgeException()
        {
        }
    }
}

#Program.cs

using System;
using Lesson05.Exceptions;
using System.Collections;
using System.Collections.Generic;

namespace Lesson05
{
    interface IRunning
    {
        void OnRunning();
    }

    class People : IRunning
    {
        public void OnRunning()
        {
            Console.WriteLine("Test running...");
        }
    }

    delegate void OnRunning();
    delegate double Calculator(double x, double y);

    class Program
    {
        static event Calculator tinhtongEvent;

        static void Main(string[] args)
        {
            //TestException();
            //Test01();
            Test02();
        }

        static void Test02()
        {
            //List
            List<int> list1 = new List<int>();
            list1.Add(123);
            list1.Add(34);

            //ArrayList -> Quan ly nhieu kieu du lieu khac nhau.
            ArrayList list2 = new ArrayList();
            list2.Add(123);
            list2.Add("test sdfdsf");
            list2.Add(true);
            list2.Add('C');

            List<Object> list3 = new List<object>();
            list3.Add(123);
            list3.Add("test sdfdsf");
            list3.Add(true);
            list3.Add('C');

            //Dictionary -> Hashmap
            Dictionary<string, string> dic = new Dictionary<string, string>();
            dic.Add("fullname", "Tran Van Diep");
            dic.Add("email", "abc@gmail.com");
            if(dic.ContainsKey("fullname"))
            {
                dic["fullname"] = "asdsadsad";
            } else
            {
                dic.Add("fullname", "ABCBABCS");
            }

            string v = dic["fullname"];
            Console.WriteLine(v);

            Testing(dic);
            Console.WriteLine("okok: " + dic["okok"]);

            //Stack
            Stack<string> stack = new Stack<string>();
            stack.Push("1");
            foreach(string s in stack)
            {
                Console.WriteLine(s);
            }
            stack.Push("2");
            foreach (string s in stack)
            {
                Console.WriteLine(s);
            }
            stack.Push("3");
            foreach (string s in stack)
            {
                Console.WriteLine(s);
            }

            string v1 = stack.Pop();
            Console.WriteLine("---" + v1);
            foreach (string s in stack)
            {
                Console.WriteLine(s);
            }

            //Queue
            Queue<string> queue = new Queue<string>();
            queue.Enqueue("1");
            foreach (string s in queue)
            {
                Console.WriteLine(s);
            }
            queue.Enqueue("2");
            foreach (string s in queue)
            {
                Console.WriteLine(s);
            }
            queue.Enqueue("3");
            foreach (string s in queue)
            {
                Console.WriteLine(s);
            }

            string v2 = queue.Dequeue();
            Console.WriteLine("---" + v2);
            foreach (string s in queue)
            {
                Console.WriteLine(s);
            }
        }

        static void Testing(Dictionary<string, string> dic)
        {
            dic.Add("okok", "ABC");
        }

        static void Test01()
        {
            People p = new People();
            p.OnRunning();

            //C1: Khoi tao delegate C# -> method anonymous
            OnRunning running1 = delegate {
                Console.WriteLine("Testing ...");
	        };
            running1();

            //C2:
            OnRunning running2 = delegate() {
                Console.WriteLine("Testing 2 ...");
            };
            running2();

            //C3:
            OnRunning running3 = () => {
                Console.WriteLine("Testing 2 ...");
            };
            running3();

            //C4:
            OnRunning running4 = () => Console.WriteLine("Testing 2 ...");
            running4();

            Calculator tong = delegate(double x, double y) {
                return x + y;
	        };
            double r = tong(3, 6);
            Console.WriteLine("Tong: " + r);

            Calculator hieu = (x, y) => {
                return x + y;
            };
            r = hieu(3, 6);
            Console.WriteLine("Hieu: " + r);

            hieu = (double x, double y) => {
                return x + y;
            };
            r = hieu(3, 6);
            Console.WriteLine("Hieu: " + r);

            hieu = (x, y) => x + y;
            r = hieu(3, 6);
            Console.WriteLine("Hieu: " + r);

            Calculator tich = new Calculator((x, y) => x * y);
            Console.WriteLine("Tich: " + tich(2, 6));

            Calculator cal = TinhTong;
            cal = new Calculator(TinhTong);
            r = cal(5, 6);
            Console.WriteLine("Tich: " + r);

            //Delegate -> Noi nhieu function lai -> chay list
            Calculator calculator = TinhTong;
            //T1
            calculator += (x, y) => {
                Console.WriteLine("Tinh tong test........");
                return x + y;
            };
            //T2
            calculator += (x, y) => {
                Console.WriteLine("Tinh hieu ----- test........");
                return x - y;
            };
            r = calculator(1, 9);
            //TinhTong(1,9), T1(1,9), T2(1,9)
            Console.WriteLine("r: " + r);

            //Event
            tinhtongEvent = TinhTong;
            tinhtongEvent = new Calculator(TinhTong);
            tinhtongEvent(2, 8);

            //Truyen param la function | methods
            TestDelegate(TinhTong);
        }

        static double TinhTong(double x, double y)
        {
            Console.WriteLine("Test tinh tong ...");
            return x + y;
        }

        static void TestDelegate(Calculator cal)
        {
            cal(2, 8);
        }

        static void TestException()
        {
            //Exception -> Logic -> 3 Crash
            int x = 0, y = 0;
            try
            {
                Console.WriteLine("Nhap X = ");
                x = int.Parse(Console.ReadLine());
            } catch (Exception ex)
            {
                Console.WriteLine("Nhap sai!!!");
            }

            try
            {
                Console.WriteLine("Nhap Y = ");
                y = int.Parse(Console.ReadLine());
            } catch(Exception e)
            {
                Console.WriteLine("Nhap sai!!!");
            }

            if(y == 0)
            {
                Console.WriteLine("Khong dc chia cho Zero");
            } else
            {
                int z = x / y;
                Console.WriteLine("z = " + z);
            }

            //Next custom exception
            Student std;

            try
            {
                std = new Student("ABC", -10, "abc@gmail.com");
                Console.WriteLine("Khoi tao thanh cong");
            } catch(AgeException ex)
            {
                Console.WriteLine("Age exception");
            } catch(EmailException ex)
            {
                Console.WriteLine("Email exception");
            } catch(Exception e)
            {
                Console.WriteLine(e.Message);
            }

            try
            {
                std = new Student("ABC", 10, "abcgmail.com");
                Console.WriteLine("Khoi tao thanh cong");
            }
            catch (AgeException ex)
            {
                Console.WriteLine("Age exception");
            }
            catch (EmailException ex)
            {
                Console.WriteLine("Email exception");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }

            try
            {
                std = new Student("ABC", 10, "abc@gmail.com");
                Console.WriteLine("Khoi tao thanh cong");
            }
            catch (AgeException ex)
            {
                Console.WriteLine("Age exception");
            }
            catch (EmailException ex)
            {
                Console.WriteLine("Email exception");
            }
            catch (Exception e)
            {
                Console.WriteLine(e.Message);
            }
        }
    }
}