# 建造者模式

属于创建型模式。
将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示。

主要用于创建一些复杂的对象，这些对象内部构建间的建造顺序通常是稳定的，但对象内部的构建通常面临着复杂的变化。

用户只需要指定需要建造的类型就可以得到它们，如果需要改变一个产品的表示，只需要新创建一个建造者即可。

# 类图

	namespace CreationalPatterns_BuilderPattern
	{
	/// <summary>
	/// 形状
	/// </summary>
	public class Shape
	{
	/// <summary>
	/// 形状
	/// </summary>
	public string ShapeName;

	/// <summary>
	/// 效果
	/// </summary>
	public string EffectName;

	/// <summary>
	/// 颜色
	/// </summary>
	public string ColorName;

	public void Show()
	{
	Console.WriteLine("Shape：" + ShapeName);
	Console.WriteLine("Effect：" + EffectName);
	Console.WriteLine("Color：" + ColorName);
	}
	}
	}

	namespace CreationalPatterns_BuilderPattern
	{
	public abstract class ShapeBuilder
	{
	/// <summary>
	/// 设置形状
	/// </summary>
	protected abstract void SetShape(Shape shape);

	/// <summary>
	/// 添加效果
	/// </summary>
	protected abstract void SetEffect(Shape shape);

	/// <summary>
	/// 添加颜色
	/// </summary>
	protected abstract void SetColor(Shape shape);

	/// <summary>
	/// 返回一个创建完成的对象
	/// </summary>
	/// <returns></returns>
	public abstract Shape GetShape();

	}
	}

	namespace CreationalPatterns_BuilderPattern
	{
	public class SquareBuilder : ShapeBuilder
	{
	public override Shape GetShape()
	{
	Shape shape = new Shape();
	SetShape(shape);
	SetColor(shape);
	SetEffect(shape);

	return shape;
	}

	protected override void SetShape(Shape shape)
	{
	shape.ShapeName = "Square";
	}

	protected override void SetColor(Shape shape)
	{
	shape.ColorName = "Red";
	}

	protected override void SetEffect(Shape shape)
	{
	shape.EffectName = "Transparent";
	}
	}
	}

	namespace CreationalPatterns_BuilderPattern
	{
	public class TriangleBuilder : ShapeBuilder
	{
	public override Shape GetShape()
	{
	Shape shape = new Shape();
	SetShape(shape);
	SetColor(shape);
	SetEffect(shape);

	return shape;
	}

	protected override void SetShape(Shape shape)
	{
	shape.ShapeName = "Triangle";
	}

	protected override void SetColor(Shape shape)
	{
	shape.ColorName = "Blue";
	}

	protected override void SetEffect(Shape shape)
	{
	shape.EffectName = "Opaque";
	}
	}
	}

	namespace CreationalPatterns_BuilderPattern
	{
	public class Program
	{
	private static void Main()
	{
	ShapeBuilder squareBuilder = new SquareBuilder();
	ShapeBuilder triangleBuilder = new TriangleBuilder();

	squareBuilder.GetShape().Show();
	Console.WriteLine();
	triangleBuilder.GetShape().Show();
	}
	}
	}

运行结果：
Shape：Square
Effect：Transparent
Color：Red

Shape：Triangle
Effect：Opaque
Color：Blue