03)Builder

    生成器模式的目的是: 分步骤构建一个复杂的对象,把构造过程从对象的表示中分离出来。
    实例代码:

//定义个交通工具类
class Vehicle
{
  private string _type;
  private Hashtable _parts = new Hashtable();
  public Vehicle(string type)
  {
    this._type = type;
  }
  //索引
  public object this[string key]
  {
    get { return this._parts[key]; }
    set { this._parts[key] = value; }
  }
  public void Show()
  {
    Console.WriteLine("---------------------------");
    Console.WriteLine("名称: {0}", this._type);
    Console.WriteLine("形状: {0}", this._parts["frame"]);
    Console.WriteLine("发动机: {0}", this._parts["engine"]);
    Console.WriteLine("轮胎数: {0}", this._parts["wheels"]);
    Console.WriteLine("车门数: {0}\n", this._parts["doors"]);
  }
}
//生成交通工具的基类
abstract class VehicleBuilder
{
  protected Vehicle vehicle;
  public Vehicle Vehicle
  {
    get { return vehicle; }
  }
  public abstract void BuildFrame();  //形状
  public abstract void BuildEngine(); //发动机
  public abstract void BuildWheels(); //轮胎数
  public abstract void BuildDoors();  //车门数
}
//生成摩托车
class MotorCycleBuilder : VehicleBuilder
{
  public override void BuildFrame()
  {
    vehicle = new Vehicle("摩托车");
    vehicle["frame"] = "摩托车形状";
  }
  public override void BuildEngine()
  {
    vehicle["engine"] = "800CC";
  }
  public override void BuildWheels()
  {
    vehicle["wheels"] = "2个";
  }
  public override void BuildDoors()
  {
    vehicle["doors"] = "N/A";
  }
}
//生成小汽车
class CarBuilder : VehicleBuilder
{
  public override void BuildFrame()
  {
    vehicle = new Vehicle("法拉利");
    vehicle["frame"] = "跑车形状";
  }
  public override void BuildEngine()
  {
    vehicle["engine"] = "4000CC";
  }
  public override void BuildWheels()
  {
    vehicle["wheels"] = "4个";
  }
  public override void BuildDoors()
  {
    vehicle["doors"] = "2门";
  }
}
//生成单车 
class ScooterBuilder : VehicleBuilder
{
  public override void BuildFrame()
  {
    vehicle = new Vehicle("单车");
    vehicle["frame"] = "自行车形状";
  }
  public override void BuildEngine()
  {
    vehicle["engine"] = "0CC";
  }
  public override void BuildWheels()
  {
    vehicle["wheels"] = "2个";
  }
  public override void BuildDoors()
  {
    vehicle["doors"] = "N/A";
  }
}
//定购类 
class Shop
{
  public void Construct(VehicleBuilder vehicleBuilder)  //生成步骤
  {
    vehicleBuilder.BuildFrame();   //生成车的形状
    vehicleBuilder.BuildEngine();  //安装发动机
    vehicleBuilder.BuildWheels();  //安装轮胎
    vehicleBuilder.BuildDoors();   //安装车门
  }
}
//测试
public class MainApp
{
  public static void Main()
  {
    Shop shop = new Shop();
    VehicleBuilder b1 = new ScooterBuilder();
    VehicleBuilder b2 = new CarBuilder();
    VehicleBuilder b3 = new MotorCycleBuilder();
    shop.Construct(b1);  //定购一辆Scooter
    b1.Vehicle.Show();
    shop.Construct(b2);  //定购一辆Car
    b2.Vehicle.Show();
    shop.Construct(b3);  //定购一辆MotorCycle
    b3.Vehicle.Show();
     Console.Read();
  }
}