1，定义

建造者模式：将一个复杂对象的构造与他的表示分离，使得同样的构造过程可以创建不同的表示

2，UML图

建造者模式

3，基本代码

namespace 建造者模式
{
    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();
            p1.Show();

            director.Construct(b2);
            Product p2 = b2.GetResult();
            p2.Show();

            Console.Read();
        }
    }

    class Director
    {
        public void Construct(Builder builder)
        {
            builder.BuildPartA();
            builder.BuildPartB();
        }
    }

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

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

        public override void BuildPartA()
        {
            product.Add("部件A");
        }

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

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

    class ConcreteBuilder2 : Builder
    {
        private Product product = new Product();
        public override void BuildPartA()
        {
            product.Add("部件X");
        }

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

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

    class Product
    {
        IList<string> parts = new List<string>();

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

        public void Show()
        {
            Console.WriteLine("\n产品 创建 ----");
            foreach (string part in parts)
            {
                Console.WriteLine(part);
            }
        }
    }


}

4，简单应用

namespace 建造者模式
{
    abstract class PersonBuilder
    {
        protected Graphics g;
        protected Pen p;

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

        public abstract void BuildHead();
        public abstract void BuildBody();
        public abstract void BuildArmLeft();
        public abstract void BuildArmRight();
        public abstract void BuildLegLeft();
        public abstract void BuildLegRight();
    }

    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);
        }
    }

    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.DrawEllipse(p, 45, 50, 40, 50);
        }

        public override void BuildArmLeft()
        {
            g.DrawLine(p, 50, 50, 30, 100);
        }

        public override void BuildArmRight()
        {
            g.DrawLine(p, 80, 50, 100, 100);
        }

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

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

    class PersonDirector
    {
        private PersonBuilder pb;
        public PersonDirector(string type, Graphics g, Pen p)
        {
            string assemblyName="建造者模式";
            object[] args = new object[2];
            args[0] = g;
            args[1] = p;

            this.pb = (PersonBuilder)Assembly.Load(assemblyName).CreateInstance(assemblyName+".Person" + type + "Builder", false, BindingFlags.Default, null, args, null, null);
        }

        public void CreatePerson()
        {
            pb.BuildHead();
            pb.BuildBody();
            pb.BuildArmLeft();
            pb.BuildArmRight();
            pb.BuildLegLeft();
            pb.BuildLegRight();
        }
    }
}

5，思考

1。如果使用了建造者模式，只需指定需要建造的类型就能得到他们，而不必知道具体的建造细节
2，建造者builder类的建造方法必须足够普遍，以便为各种类型的具体建造者构造
3，建造者模式是在创建复杂对象的算法应该独立该对象的组成部分以及他们的装配方式时使用的模式