建造者模式 - 設計模式學習

時間 2019-12-10

標籤建造者模式設計學習简体版

原文原文鏈接

　　建造者模式(Builder)，將一個複製對象的構建與它的表示分離，使得一樣的構建過程能夠建立不一樣的表示。javascript

　　建造者模式的UML圖：html

　　　　Builder是爲建立一個Product對象的各個部件指定的抽象接口。java

　　　　ConcreteBuilder是具體的建造者，實現Builder接口，構造和裝備各個部件。git

　　　　Product是產品角色，也就是具體的產品。算法

　　　　Director是指揮者，它是構建一個使用Builder接口的對象。設計模式

　　　　如下給出建造者模式的基本代碼結構：ide

namespace ConsoleApplication1
{
    //Product類
    class Product
    {
        IList<string> parts = new List<string>();

        public void Add(string part)
        {
            parts.Add(part);
        }

        public void Show()
        {
            Console.WriteLine("產品 建立 --- ");
            foreach (string part in parts)
            {
                Console.WriteLine(part);
            }
        }
    }

    //Builder類
    abstract class Builder
    {
        public abstract void BuildPartA();
        public abstract void BuildPartB();
        public abstract Product GetResult();
    }

    //ConcreteBuild1類
    class ConcreteBuilder1 : Builder
    {
        private Product product = new Product();

        public override void BuildPartA()   //建造具體的兩個部件是部件A和部件B
        {
            product.Add("部件A");
        }

        public override void BuildPartB()
        {
            product.Add("部件B");
        }

        public override Product GetResult()
        {
            return product;
        }
    }

    //ConcreteBuild1類
    class ConcreteBuilder2 : Builder
    {
        private Product product = new Product();

        public override void BuildPartA()   //建造兩個部件是部件X和部件Y
        {
            product.Add("部件X");
        }

        public override void BuildPartB()
        {
            product.Add("部件Y");
        }

        public override Product GetResult()
        {
            return product;
        }
    }

    //Director指揮者類
    class Director
    {
        public void Construct(Builder builder)
        {
            builder.BuildPartA();   //用來指揮建造過程
            builder.BuildPartB();
        }
    }

    class Program
    {
        static void Main(string[] args)
        {
            Director director = new Director(); 
            Builder b1 = new ConcreteBuilder1();
            Builder b2 = new ConcreteBuilder2();

            director.Construct(b1);
            Product p1 = b1.GetResult();        //指揮者用ConcreteBuilder1的方法來建造產品
            p1.Show();

            director.Construct(b2);

            Product p2 = b2.GetResult();　　　　//指揮者用ConcreteBuilder2的方法來建造產品
            p2.Show();

            Console.ReadKey();
        }
    }  
}

　　回到《大話設計模式》裏的造人的例子：函數

namespace WindowsFormsApplication1
{
    public partial class Form1 : Form
    {
        public Form1()
        {
            InitializeComponent();
        }

        private void Form1_Load(object sender, EventArgs e)
        {

        }

        private void button1_Click(object sender, EventArgs e)
        {
            Pen p = new Pen(Color.Blue);
            PersonThinBuilder ptb = new PersonThinBuilder(pictureBox1.CreateGraphics(), p);
            PersonDirector pdThin = new PersonDirector(ptb);
            pdThin.CreatePerson();

            PersonFatBuilder pfb = new PersonFatBuilder(pictureBox2.CreateGraphics(), p);
            PersonDirector pdFat = new PersonDirector(pfb);
            pdFat.CreatePerson();
        }
    }

    abstract class PersonBuilder
    {
        protected Graphics g;
        protected Pen p;

        public PersonBuilder(Graphics g, Pen p)
        {
            this.g = g;
            this.p = p;
        }

        //造人都必需要有頭，身體，左右手，左右腳，都必須共有的提取出來做爲抽象方法限制其子類必須有
        public abstract void BuildHead();
        public abstract void BuildBody();
        public abstract void BuildArmLeft();
        public abstract void BuildArmRight();
        public abstract void BuildLegLeft();
        public abstract void BuildLegRight();
    }

    //瘦人建造類,具體的建造過程
    class PersonThinBuilder : PersonBuilder
    {
        public PersonThinBuilder(Graphics g, Pen p) : base(g, p)
        {

        }

        public override void BuildHead()
        {
            g.DrawEllipse(p, 50, 20, 30, 30);
        }

        public override void BuildBody()
        {
            g.DrawRectangle(p, 60, 50, 10, 50);
        }

        public override void BuildArmLeft()
        {
            g.DrawLine(p, 60, 50, 40, 100);
        }

        public override void BuildArmRight()
        {
            g.DrawLine(p, 70, 50, 90, 100);
        }

        public override void BuildLegLeft()
        {
            g.DrawLine(p, 60, 100, 45, 150);
        }

        public override void BuildLegRight()
        {
            g.DrawLine(p, 70, 100, 85, 150);
        }
    }

    //肥人建造類,具體的建造過程
    class PersonFatBuilder : PersonBuilder
    {
        public PersonFatBuilder(Graphics g, Pen p): base(g, p)
        {

        }

        public override void BuildHead()
        {
            g.DrawEllipse(p, 50, 20, 30, 30);
        }

        public override void BuildBody()
        {
            g.DrawRectangle(p, 45, 50, 40, 50);
        }

        public override void BuildArmLeft()
        {
            g.DrawLine(p, 60, 50, 40, 100);
        }

        public override void BuildArmRight()
        {
            g.DrawLine(p, 70, 50, 90, 100);
        }

        public override void BuildLegLeft()
        {
            g.DrawLine(p, 60, 100, 45, 150);
        }

        public override void BuildLegRight()
        {
            g.DrawLine(p, 70, 100, 85, 150);
        }
    }

    //指揮者類Director
    class PersonDirector
    {
        private PersonBuilder pb;
        public PersonDirector(PersonBuilder pb)
        {
            this.pb = pb;
        }

        public void CreatePerson()　　//裝配方法 控制裝配過程
        {
            pb.BuildHead();
            pb.BuildBody();
            pb.BuildArmLeft();
            pb.BuildArmRight();
            pb.BuildLegLeft();
            pb.BuildLegRight();
        }
    }
}