class1.cs

《深入浅出设计模式》的完整源代码

namespace libraryItem
{
	using System;
	using System.Collections;
	// 定义抽象LibaryItem类
	abstract class LibraryItem
	{
		private int numCopies;
		// 属性
		public int NumCopies
		{
			get{ return numCopies; }
			set{ numCopies = value; }
		}
		public abstract void Display();
	}
	//定义具体的部件类-Book。
	class Book : LibraryItem
	{
		private string author;
		private string title;
		public Book(string author,string title,int numCopies)
		{
			this.author = author;
			this.title = title;
			this.NumCopies = numCopies;
		}
		public override void Display()
		{
			Console.WriteLine( "\n书 ------ " );
			Console.WriteLine( " 作者: {0}", author );
			Console.WriteLine( " 书名: {0}", title );
			Console.WriteLine( " # 数量: {0}", NumCopies );
		}
	}
	//定义具体的部件类-Video
	class Video : LibraryItem
	{
		private string director;
		private string title;
		private int playTime;
		public Video( string director, string title,
			int numCopies, int playTime )
		{
			this.director = director;
			this.title = title;
			this.NumCopies = numCopies;
			this.playTime = playTime;
		}
		public override void Display()
		{
			Console.WriteLine( "\n影像 ----- " );
			Console.WriteLine( " 导演: {0}", director );
			Console.WriteLine( " 片名: {0}", title );
			Console.WriteLine( " # 数量: {0}", NumCopies );
			Console.WriteLine( " 播放时间: {0}", playTime );
		}
	}
	// 定义抽象装饰类
	abstract class Decorator : LibraryItem
	{
		protected LibraryItem libraryItem;
		public Decorator ( LibraryItem libraryItem )
		{
			this.libraryItem = libraryItem;
		}
		public override void Display()
		{
			libraryItem.Display();
		}
	}
	// 定义具体装饰类
	class Borrowable : Decorator
	{
		protected ArrayList borrowers = new ArrayList();
		//调用父类的构造函数
		public Borrowable( LibraryItem libraryItem )
			: base( libraryItem ) {}
		public void BorrowItem( string name )
		{
			borrowers.Add( name );
			libraryItem.NumCopies--;
		}
		public void ReturnItem( string name )
		{
			borrowers.Remove( name );
			libraryItem.NumCopies++;
		}
		public override void Display()
		{
			base.Display();
			foreach( string borrower in borrowers )
				Console.WriteLine( " 借出人: {0}", borrower );
		}
	} 
	/// <summary>
	/// 装饰模式应用测试
	/// </summary>
	public class DecoratorApp
	{
		public static void Main( string[] args )
		{
			//创建Book及Video,并显示出来
			Book book = new Book( "Schnell", "My Home", 10 );
			Video video = new Video( "Spielberg",
				"Schindler's list", 23, 60 );
			book.Display();
			video.Display();
			// 增加video的borrowable属性,然后借出并显示
			Console.WriteLine( "\n影像增加可借属性:" );
			Borrowable borrowvideo = new Borrowable( video );
			borrowvideo.BorrowItem( "张三" );
			borrowvideo.BorrowItem( "李四" );
			borrowvideo.Display();
			Console.Read();
		}
	}  
}