Interpreter 设计模式 实现代码

1、开发环境 vs2005 代码经测试无误

2、此代码根据李建忠老师的视频代码编写

3、注释一条令人迷惑的代码

4、实现YiExpression

 

using System;
using System.Collections.Generic;
using System.Text;
using System.Collections;

namespace Interpreter
{
    class Program
    {
        static void Main(string[] args)
        {
            string roman = "五亿二十四万三千四百零二";
            
            Context context = new Context(roman);
            ArrayList tree = new ArrayList();
            tree.Add(new GeExpression());
            tree.Add(new ShiExpression());
            tree.Add(new BaiExpression());
            tree.Add(new QianExpression());
            tree.Add(new WanExpression());
            tree.Add(new YiExpression());
            
            foreach(Expression exp in tree)
            {
                exp.Interpret(context);
            }
            Console.WriteLine("{0}={1}", roman, context.Data);

            Console.Read();

        }
    }

    public abstract class Expression
    {
        public Hashtable hstMap = new Hashtable();
        public Expression()
        {
            hstMap.Add("一", 1);
            hstMap.Add("二",2 );
            hstMap.Add("三",3 );
            hstMap.Add("四",4 );
            hstMap.Add("五",5 );
            hstMap.Add("六",6 );
            hstMap.Add("七", 7);
            hstMap.Add("八", 8);
            hstMap.Add("九", 9);
        }
        public abstract string GetPostfix();
        public abstract int GetMultiplier();
        public virtual int GetLength()
        {
            return this.GetPostfix().Length + 1;
        }

        public virtual void Interpret(Context context)
        {
            if (context.Statement.Length==0)
            {
                return;
            }
            foreach (string key in hstMap.Keys)
            {
                int value = (int)hstMap[key];
                if (context.Statement.EndsWith(key+this.GetPostfix()))
                {
                    context.Data += value * this.GetMultiplier();
                    context.Statement = context.Statement.Substring(0, context.Statement.Length - this.GetLength());
                }
                if (context.Statement.EndsWith("零"))
                {
                    context.Statement = context.Statement.Substring(0, context.Statement.Length-1);
                }
            }
            
        }
    }//class Expression

    public class GeExpression:Expression
    {
        public override string GetPostfix()
        {
            return "";
        }
        public override int GetMultiplier()
        {
            return 1;
        }
    }
    public class ShiExpression : Expression
    {
        public override string GetPostfix()
        {
            return "十";
        }
        public override int GetMultiplier()
        {
            return 10;
        }
    }
    public class BaiExpression : Expression
    {
        public override string GetPostfix()
        {
            return "百";
        }
        public override int GetMultiplier()
        {
            return 100;
        }
    }
    public class QianExpression : Expression
    {
        public override string GetPostfix()
        {
            return "千";
        }
        public override int GetMultiplier()
        {
            return 1000;
        }
    }

    /// <summary>
    /// 万和个十百千不一样
    /// </summary>
    public class WanExpression : Expression
    {
        public override string GetPostfix()
        {
            return "万";
        }
        public override int GetMultiplier()
        {
            return 10000;
        }
        public override void Interpret(Context context)
        {
            if (context.Statement.Length == 0)
            {
                return;
            }

            ArrayList tree = new ArrayList();
            tree.Add(new GeExpression());
            tree.Add(new ShiExpression());
            tree.Add(new BaiExpression());
            tree.Add(new QianExpression());

           //foreach(string key in hstMap.Keys)   //此行代码实属无用，个人愚见！！！！！！！！！！！！！！！！
            {
                if(context.Statement.EndsWith(this.GetPostfix()))
                {
                    int temp = context.Data;
                    context.Data = 0;
                    context.Statement = context.Statement.Substring(0, context.Statement.Length - 1);
                    
                    foreach(Expression exp in tree)
                    {
                        exp.Interpret(context);                       
                    }
                    
                    context.Data = temp + this.GetMultiplier() * context.Data;
                }
            }

 

        }

    }

 

/// 亿和万类似
    public class YiExpression : Expression
    {
        public override string GetPostfix()
        {
            return "亿";
        }
        public override int GetMultiplier()
        {
            return 100000000;
        }
        public override void Interpret(Context context)
        {
            if (context.Statement.Length == 0)
            {
                return;
            }

            ArrayList tree = new ArrayList();
            tree.Add(new GeExpression());
            tree.Add(new ShiExpression());
            tree.Add(new BaiExpression());
            tree.Add(new QianExpression());
            tree.Add(new WanExpression());

           // foreach (string key in hstMap.Keys)
            {
                if (context.Statement.EndsWith(this.GetPostfix()))
                {
                    int temp = context.Data;
                    context.Data = 0;
                    context.Statement = context.Statement.Substring(0, context.Statement.Length - 1);

                    foreach (Expression exp in tree)
                    {
                        exp.Interpret(context);
                    }

                    context.Data = temp + this.GetMultiplier() * context.Data;
                }
            }

        }

    }

 

    public class Context
    {
        private string statement;
        private int data;
        public Context(string statement)
        {
            this.statement=statement;
        }
        public string Statement
        {
            get { return statement; }
            set { statement = value; }
        }
        public int Data
        {
            get { return data; }
            set { data = value; }
        }
    }

}