设计模式学习笔记--解释器模式

using System;

namespace Interpreter
{
    /// <summary> 
    /// 作者：bzyzhang
    /// 时间：2016/6/3 19:42:24 
    /// 博客地址：http://www.cnblogs.com/bzyzhang/
    /// Context说明：本代码版权归bzyzhang所有，使用时必须带上bzyzhang博客地址 
    /// </summary> 
    public class Context
    {
        private string text;

        public string PlayText
        {
            get { return text; }
            set { text = value; }
        }
    }
}

using System;

namespace Interpreter
{
    /// <summary> 
    /// 作者：bzyzhang
    /// 时间：2016/6/3 19:41:33 
    /// 博客地址：http://www.cnblogs.com/bzyzhang/
    /// AbstractExpression说明：本代码版权归bzyzhang所有，使用时必须带上bzyzhang博客地址 
    /// </summary> 
    public abstract class AbstractExpression
    {
        public void Interpret(Context context)
        {
            if (context.PlayText.Length == 0)
            {
                return; 
            }
            else
            {
                string playKey = context.PlayText.Substring(0,1);
                context.PlayText = context.PlayText.Substring(2);
                double playValue = Convert.ToDouble(context.PlayText.Substring(0,context.PlayText.IndexOf(" ")));
                context.PlayText = context.PlayText.Substring(context.PlayText.IndexOf(" ")+1);

                Execute(playKey,playValue);
            }
        }

        public abstract void Execute(string key,double value);
    }
}

using System;

namespace Interpreter
{
    /// <summary> 
    /// 作者：bzyzhang
    /// 时间：2016/6/3 19:59:36 
    /// 博客地址：http://www.cnblogs.com/bzyzhang/
    /// Note说明：本代码版权归bzyzhang所有，使用时必须带上bzyzhang博客地址 
    /// </summary> 
    public class Note : AbstractExpression
    {
        public override void Execute(string key, double value)
        {
            string note = "";
            switch (key)
            {
                case "C":
                    note = "1";
                    break;
                case "D":
                    note = "2";
                    break;
                case "E":
                    note = "3";
                    break;
                case "F":
                    note = "4";
                    break;
                case "G":
                    note = "5";
                    break;
                case "A":
                    note = "6";
                    break;
                case "B":
                    note = "7";
                    break;
            }
            Console.WriteLine("{0}", note);
        }
    }
}

using System;

namespace Interpreter
{
    /// <summary> 
    /// 作者：bzyzhang
    /// 时间：2016/6/3 20:02:48 
    /// 博客地址：http://www.cnblogs.com/bzyzhang/
    /// Scale说明：本代码版权归bzyzhang所有，使用时必须带上bzyzhang博客地址 
    /// </summary> 
    public class Scale : AbstractExpression
    {
        public override void Execute(string key, double value)
        {
            string scale = "";

            switch (Convert.ToInt32(value))
            {
                case 1:
                    scale = "低音";
                    break;
                case 2:
                    scale = "中音";
                    break;
                case 3:
                    scale = "高音";
                    break;
            }

            Console.WriteLine("{0}", scale);
        }
    }
}

using System;
using System.Collections.Generic;

namespace Interpreter
{
    class Program
    {
        static void Main(string[] args)
        {
            Context context = new Context();
            context.PlayText = "O 2 E 0.5 G 0.5 A 3 E 0.5 G 0.5";

            AbstractExpression exp = null;

            try
            {
                while (context.PlayText.Length > 0)
                {
                    string str = context.PlayText.Substring(0, 1);
                    switch (str)
                    {
                        case "O":
                            exp = new Scale();
                            break;
                        case "C":
                        case "D":
                        case "E":
                        case "F":
                        case "A":
                        case "B":
                        case "P":
                            exp = new Note();
                            break;
                    }
                    exp.Interpret(context);
                }
            }
            catch (Exception ex)
            {
                Console.WriteLine(ex.Message);
            }
        }
    }
}