CSharp: Builder Pattern in donet core 3

 

 /// <summary>
    /// Car is a ConcreteBuilder
    ///  生成器 Builder Pattern 
    ///  geovindu eidit
    /// </summary>
    class Car : IBuilder
    {
        /// <summary>
        /// 
        /// </summary>
        private string brandName;
        /// <summary>
        /// 
        /// </summary>
        private Product product;
        /// <summary>
        /// 
        /// </summary>
        /// <param name="brand"></param>
        public Car(string brand)
        {
            product = new Product();
            this.brandName = brand;
        }
        /// <summary>
        /// 
        /// </summary>
        public void StartUpOperations()
        {   //Starting with brandname
            product.Add("-----------");
            product.Add($"Car model name :{this.brandName}");
        }

        /// <summary>
        /// 
        /// </summary>
        public void BuildBody()
        {
            product.Add("This is a body of a Car");
        }

        /// <summary>
        /// 
        /// </summary>
        public void InsertWheels()
        {
            product.Add("4 wheels are added");
        }
        /// <summary>
        /// 
        /// </summary>
        public void AddHeadlights()
        {
            product.Add("2 Headlights are added");
        }
        /// <summary>
        /// 
        /// </summary>
        public void EndOperations()
        {
            product.Add("-----------");
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public Product GetVehicle()
        {
            return product;
        }
    }

　　

    /// <summary>
    ///  "Director"
    ///  生成器 Builder Pattern 
    ///  geovindu eidit
    /// </summary>
    class Director
    {

        /// <summary>
        /// 
        /// </summary>
        private IBuilder builder;

        /* 
         * A series of steps.In real life, these steps 
         * can be much more complex.
         */

        /// <summary>
        /// 
        /// </summary>
        /// <param name="builder"></param>
        public void Construct(IBuilder builder)
        {

            this.builder = builder;
       
            builder.StartUpOperations();

            builder.BuildBody();

            builder.InsertWheels();

            builder.AddHeadlights();

            builder.EndOperations();
        }
    }

　　

    ///<summary>
    ///The common interface
    ///生成器 Builder Pattern 
    ///geovindu eidit
    /// </summary> 
    interface IBuilder
    {
        /// <summary>
        /// 
        /// </summary>
        void StartUpOperations();
        /// <summary>
        /// 
        /// </summary>
        void BuildBody();
        /// <summary>
        /// 
        /// </summary>
        void InsertWheels();
        /// <summary>
        /// 
        /// </summary>
        void AddHeadlights();
        /// <summary>
        /// 
        /// </summary>
        void EndOperations();
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        Product GetVehicle();
        //An interface cannot contain instance field
        //Product product;//error
    }

　　

 /// <summary>
    /// Motorcycle is another ConcreteBuilder
    /// 生成器 Builder Pattern 
    /// geovindu eidit
    /// </summary>
    class Motorcycle : IBuilder
    {

        /// <summary>
        /// 
        /// </summary>
        private string brandName;

        /// <summary>
        /// 
        /// </summary>
        private Product product;

        /// <summary>
        /// 
        /// </summary>
        /// <param name="brand"></param>
        public Motorcycle(string brand)
        {
            product = new Product();
            this.brandName = brand;
        }
        /// <summary>
        /// 
        /// </summary>
        public void StartUpOperations()
        {
            product.Add("_________________");
        }
        /// <summary>
        /// 
        /// </summary>
        public void BuildBody()
        {
            product.Add("This is a body of a Motorcycle");
        }

        /// <summary>
        /// 
        /// </summary>
        public void InsertWheels()
        {
            product.Add("2 wheels are added");
        }
        /// <summary>
        /// 
        /// </summary>
        public void AddHeadlights()
        {
            product.Add("1 Headlights are added");
        }
        /// <summary>
        /// 
        /// </summary>
        public void EndOperations()
        {
            //Finishing up with brandname
            product.Add($"Motorcycle model name :{this.brandName}");
            product.Add("_________________");
        }
        /// <summary>
        /// 
        /// </summary>
        /// <returns></returns>
        public Product GetVehicle()
        {
            return product;
        }
    }

　　

    /// <summary>
    ///  "Product"
    ///  生成器 Builder Pattern 
    ///  geovindu eidit
    /// </summary>
    class Product
    {
        // You can use any data structure that you prefer e.g.List<string> etc.
        /// <summary>
        /// 
        /// </summary>
        private LinkedList<string> parts;
        /// <summary>
        /// 
        /// </summary>
        public Product()
        {
            parts = new LinkedList<string>();
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="part"></param>
        public void Add(string part)
        {
            //Adding parts
            parts.AddLast(part);
        }
        /// <summary>
        /// 
        /// </summary>
        public void Show()
        {
            Console.WriteLine("\nProduct completed as below :");
            foreach (string part in parts)
                Console.WriteLine(part);
        }
    }

　　

  /// <summary>
    /// 生成器 Builder Pattern 
    /// geovindu eidit
    /// </summary>
    public class Person
    {
        public string Name, Position;

        public override string ToString()
        {
            return $"{nameof(Name)}: {Name}, {nameof(Position)}: {Position}";
        }
    }
    /// <summary>
    /// 生成器 Builder Pattern 
    /// </summary>
    /// <typeparam name="TSubject"></typeparam>
    /// <typeparam name="TSelf"></typeparam>
    public abstract class FunctionalBuilder<TSubject, TSelf>
      where TSelf : FunctionalBuilder<TSubject, TSelf>
      where TSubject : new()
    {
        /// <summary>
        /// 
        /// </summary>
        private readonly List<Func<TSubject, TSubject>> actions
          = new List<Func<TSubject, TSubject>>();
        /// <summary>
        /// 
        /// </summary>
        /// <param name="action"></param>
        /// <returns></returns>
        public TSelf Do(Action<TSubject> action)
          => AddAction(action);
        /// <summary>
        /// 
        /// </summary>
        /// <param name="action"></param>
        /// <returns></returns>
        private TSelf AddAction(Action<TSubject> action)
        {
            actions.Add(p => { action(p); return p; });
            return (TSelf)this;
        }
        public TSubject Build()
          => actions.Aggregate(new TSubject(), (p, f) => f(p));
    }
    /// <summary>
    /// 生成器 Builder Pattern 
    /// </summary>
    public sealed class PersonBuilder
      : FunctionalBuilder<Person, PersonBuilder>
    {
        /// <summary>
        /// 
        /// </summary>
        /// <param name="name"></param>
        /// <returns></returns>
        public PersonBuilder Called(string name)
          => Do(p => p.Name = name);
    }
    /// <summary>
    /// 生成器 Builder Pattern 
    /// </summary>
    public static class PersonBuilderExtensions
    {

        /// <summary>
        /// 
        /// </summary>
        /// <param name="builder"></param>
        /// <param name="position"></param>
        /// <returns></returns>
        public static PersonBuilder WorksAsA
          (this PersonBuilder builder, string position)
        {
            builder.Do(p => p.Position = position) ;
            return builder;
        }
    }

　　

  /// <summary>
    /// 生成器 Builder Pattern 
    /// geovindu eidit
    /// </summary>
    public class MailService
    {

        /// <summary>
        /// 
        /// </summary>
        public class EmailBuilder
        {
            /// <summary>
            /// 
            /// </summary>
            public class Email
            {
                public string From, To, Subject, Body;

                public override string ToString()
                {
                    return $"{nameof(From)}: {From}, {nameof(To)}: {To}, {nameof(Subject)}: {Subject}, {nameof(Body)}: {Body}";
                }
            }
            //
            private readonly Email email;
            /// <summary>
            /// 
            /// </summary>
            /// <param name="email"></param>
            public EmailBuilder(Email email) => this.email = email;
            /// <summary>
            /// 
            /// </summary>
            /// <param name="from"></param>
            /// <returns></returns>
            public EmailBuilder From(string from)
            {
                email.From = from;
                return this;
            }
            /// <summary>
            /// 
            /// </summary>
            /// <param name="to"></param>
            /// <returns></returns>
            public EmailBuilder To(string to)
            {
                email.To = to;
                return this;
            }
            /// <summary>
            /// 
            /// </summary>
            /// <param name="subject"></param>
            /// <returns></returns>
            public EmailBuilder Subject(string subject)
            {
                email.Subject = subject;
                return this;
            }
            /// <summary>
            /// 
            /// </summary>
            /// <param name="body"></param>
            /// <returns></returns>
            public EmailBuilder Body(string body)
            {
                email.Body = body;
                return this;
            }
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="email"></param>
        private void SendEmailInternal(EmailBuilder.Email email) {

            Console.WriteLine(email.ToString());
        }
        /// <summary>
        /// 
        /// </summary>
        /// <param name="builder"></param>
        public void SendEmail(Action<EmailBuilder> builder)
        {
            var email = new EmailBuilder.Email();
            builder(new EmailBuilder(email));
            SendEmailInternal(email);
        }
    }

　　

   /// <summary>
    /// 生成器 Builder Pattern 
    /// geovindu eidit
    /// </summary>
    public class Person
    {
        public string Name;

        public string Position;

        public DateTime DateOfBirth;

        public class Builder : PersonBirthDateBuilder<Builder>
        {
            internal Builder() { }
        }

        public static Builder New => new Builder();

        public override string ToString()
        {
            return $"{nameof(Name)}: {Name}, {nameof(Position)}: {Position}";
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public abstract class PersonBuilder
    {
        protected Person person = new Person();

        public Person Build()
        {
            return person;
        }
    }
    /// <summary>
    /// 
    /// </summary>
    /// <typeparam name="SELF"></typeparam>
    public class PersonInfoBuilder<SELF> : PersonBuilder
      where SELF : PersonInfoBuilder<SELF>
    {
        public SELF Called(string name)
        {
            person.Name = name;
            return (SELF)this;
        }
    }
    /// <summary>
    /// 
    /// </summary>
    /// <typeparam name="SELF"></typeparam>
    public class PersonJobBuilder<SELF>
      : PersonInfoBuilder</*PersonJobBuilder<SELF>*/SELF>
      where SELF : PersonJobBuilder<SELF>
    {
        public SELF WorksAsA(string position)
        {
            person.Position = position;
            return (SELF)this;
        }
    }

    // here's another inheritance level
    // note there's no PersonInfoBuilder<PersonJobBuilder<PersonBirthDateBuilder<SELF>>>!
    /// <summary>
    /// 
    /// </summary>
    /// <typeparam name="SELF"></typeparam>
    public class PersonBirthDateBuilder<SELF>
      : PersonJobBuilder<SELF>
      where SELF : PersonBirthDateBuilder<SELF>
    {
        public SELF Born(DateTime dateOfBirth)
        {
            person.DateOfBirth = dateOfBirth;
            return (SELF)this;
        }
    }

　　

 /// <summary>
    /// 生成器 Builder Pattern 
    /// geovindu eidit
    /// </summary>
    public class Person
    {
        public Person()
        {
            Console.WriteLine("Creating an instance of Person");
        }

        // address
        public string StreetAddress, Postcode, City;

        // employment info
        public string CompanyName, Position;

        public int AnnualIncome;

        public override string ToString()
        {
            return $"{nameof(StreetAddress)}: {StreetAddress}, {nameof(Postcode)}: {Postcode}," +
                   $" {nameof(City)}: {City}, {nameof(CompanyName)}: {CompanyName}," +
                   $" {nameof(Position)}: {Position}, {nameof(AnnualIncome)}: {AnnualIncome}";
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public class PersonBuilder // facade 
    {
        // the object we're going to build
        protected Person person;

        public PersonBuilder() => person = new Person();
        protected PersonBuilder(Person person) => this.person = person;

        public PersonAddressBuilder Lives => new PersonAddressBuilder(person);
        public PersonJobBuilder Works => new PersonJobBuilder(person);

        public static implicit operator Person(PersonBuilder pb)
        {
            return pb.person;
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public class PersonJobBuilder : PersonBuilder
    {
        public PersonJobBuilder(Person person) : base(person) { }

        public PersonJobBuilder At(string companyName)
        {
            person.CompanyName = companyName;
            return this;
        }

        public PersonJobBuilder AsA(string position)
        {
            person.Position = position;
            return this;
        }

        public PersonJobBuilder Earning(int annualIncome)
        {
            person.AnnualIncome = annualIncome;
            return this;
        }
    }
    /// <summary>
    /// 
    /// </summary>
    public class PersonAddressBuilder : PersonBuilder
    {
        public PersonAddressBuilder(Person person) : base(person) { }

        public PersonAddressBuilder At(string streetAddress)
        {
            person.StreetAddress = streetAddress;
            return this;
        }

        public PersonAddressBuilder WithPostcode(string postcode)
        {
            person.Postcode = postcode;
            return this;
        }

        public PersonAddressBuilder In(string city)
        {
            person.City = city;
            return this;
        }
    }

　　

调用：、

  //生成器 Builder Pattern 
            Console.WriteLine("***Builder Pattern Demo.***");
            //
            Director director = new Director();
            //
            IBuilder b1 = new Car("福特");
            //
            IBuilder b2 = new Motorcycle("比亚迪");
            // Making Car
            director.Construct(b1);
            //
            Product p1 = b1.GetVehicle();
            p1.Add("geovindu");
            p1.Add("天下为公");
            //
            p1.Show();

            //Making Motorcycle
            //
            director.Construct(b2);
            //
            Product p2 = b2.GetVehicle();
            p2.Add("Geovin Du");
            //
            p2.Show();

          //  Console.ReadLine();


            var b = new PersonBuilder();
            var p = b.Called("Geovin 。。。Du")
              .WorksAsA("软件开发者")
              .Build();

            Console.WriteLine(p.ToString());

            //
            var ms = new MailService();
            ms.SendEmail(email => email.From("geovindu@dusystem.com")
                .To("geovin@dusystem.com")
                .Body("Hello, how are you? Geovin Du."));

            var me = BuilderPattern.Inheritance.Person.New
                .Called("六福齐天")
                .WorksAsA("布心路")
                .Born(DateTime.UtcNow)
                .Build();
            Console.WriteLine(me);
            //
            var pb = new BuilderPatternFacets.PersonBuilder();
            BuilderPatternFacets.Person person = pb
              .Lives
                .At("10086 Buxin Road")
                .In("Shenzhen")
                .WithPostcode("518019")
              .Works
                .At("水贝珠宝")
                .AsA("工程师")
                .Earning(8123000);

            Console.WriteLine(person);

　　

输出：

***Builder Pattern Demo.***

Product completed as below :
-----------
Car model name :福特
This is a body of a Car
4 wheels are added
2 Headlights are added
-----------
geovindu
天下为公

Product completed as below :
_________________
This is a body of a Motorcycle
2 wheels are added
1 Headlights are added
Motorcycle model name :比亚迪
_________________
Geovin Du
Name: Geovin 。。。Du, Position: 软件开发者
From: geovindu@dusystem.com, To: geovin@dusystem.com, Subject: , Body: Hello, how are you? Geovin Du.
Name: 六福齐天, Position: 布心路
Creating an instance of Person
StreetAddress: 10086 Buxin Road, Postcode: 518019, City: Shenzhen, CompanyName: 水贝珠宝, Position: 工程师, AnnualIncome: 8123000