关于使用“状态模式”做工作流概要。

最近，以前一名同事问了一下工作流的事情，我现在将太概的模式写一下。

临时写的，可能有点乱，如果需要创建一个新的工作流模板的时候请新建一个工作流序列类，职责单一便于维护。

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

namespace WF
{
    /// <summary>
    /// 工程名称：通过工作流状态进行工作流管理
    /// <para>Author：Evan Lee</para>
    /// <para>编写时间：2011-05-08</para>
    /// <para>博客地址：http://www.cnblogs.com/magic_evan</para>
    /// </summary>
    class Program
    {
        /// <summary>
        /// 通过工作流状态进行工作流管理
        /// </summary>
        /// <param name="args"></param>
        static void Main(string[] args)
        {
            int start = 0;
            while (true)
            {//模板方式的工作流可以编写成模板工厂类的方式
                int.TryParse(Console.ReadLine(), out start);
                Work work = null;
               Dictionary<int, int> stepList = new Dictionary<int, int>();//工作流模板的每一步的的状态<工作流步骤,工作流状态>
                switch (start)
                {
                    case 1://输入1的时候启用第1个工作流的模板
                        work = new Work(1);
                        stepList.Add(1, 0);
                        stepList.Add(2, 0);
                        work.StepList = stepList;
                        break;
                    case 2://输入2的时候启用第2个工作流的模板
                        work = new Work(2);
                        stepList.Add(1, 1);
                        stepList.Add(2, 0);
                        stepList.Add(3, 0);
                        work.StepList = stepList;
                        break;
                    default: return;//其它跳出
                }
                work.DoWork();
            }
        }
    }

    //工作流抽象状态
    public abstract class State
    {
        public abstract void DoWork(Work w);
    }

    //工作流1
    public class wf1 : State
    {
        public override void DoWork(Work w)
        {
            if (w.IsStop)
                return;
            if (w.StepList[w.CurrentStep] > 0)
            {
                Console.WriteLine("{0}步工作流完成！显示内容", w.CurrentStep = w.CurrentStep - 1);
            }
            else
            {
                Console.WriteLine("{0}步工作流未完成！显示输入内容", w.CurrentStep = w.CurrentStep - 1);
                w.IsStop = true;
            }

            w.SetState(new wf1_1());
            w.DoWork();
        }
    }
    //工作流1-1
    public class wf1_1 : State
    {
        public override void DoWork(Work w)
        {
            if (w.IsStop)
                return;
            if (w.StepList[w.CurrentStep] > 0)
            {
                Console.WriteLine("{0}步工作流完成！显示内容", w.CurrentStep = w.CurrentStep - 1);
            }
            else
            {
                Console.WriteLine("{0}步工作流未完成！显示输入内容", w.CurrentStep = w.CurrentStep - 1);
                w.IsStop = true;
            }
            w.SetState(new wfend());
            w.DoWork();
        }
    }
    //工作流2
    public class wf2 : State
    {
        public override void DoWork(Work w)
        {
            if (w.IsStop)
                return;
            if (w.StepList[w.CurrentStep] > 0)
            {
                Console.WriteLine("{0}步工作流完成！显示内容", w.CurrentStep = w.CurrentStep - 1);
            }
            else
            {
                Console.WriteLine("{0}步工作流未完成！显示输入内容", w.CurrentStep = w.CurrentStep - 1);
                w.IsStop = true;
            }
            w.SetState(new wf2_1());
            w.DoWork();
        }
    }
    //工作流2-1
    public class wf2_1 : State
    {
        public override void DoWork(Work w)
        {
            if (w.IsStop)
                return;
            if (w.StepList[w.CurrentStep] > 0)
            {
                Console.WriteLine("{0}步工作流完成！显示内容", w.CurrentStep = w.CurrentStep - 1);
            }
            else
            {
                Console.WriteLine("{0}步工作流未完成！显示输入内容", w.CurrentStep = w.CurrentStep - 1);
                w.IsStop = true;
            }
            w.SetState(new wf2_2());
            w.DoWork();
        }
    }
    //工作流2-2
    public class wf2_2 : State
    {
        public override void DoWork(Work w)
        {
            if (w.IsStop)
                return;
            if (w.StepList[w.CurrentStep] > 0)
            {
                Console.WriteLine("{0}步工作流完成！显示内容", w.CurrentStep = w.CurrentStep - 1);
            }
            else
            {
                Console.WriteLine("{0}步工作流未完成！显示输入内容", w.CurrentStep = w.CurrentStep - 1);
                w.IsStop = true;
            }
            w.SetState(new wfend());
            w.DoWork();
        }
    }

    public class wfend : State
    {
        public override void DoWork(Work w)
        {
            Console.WriteLine("工作流完成！显示内容");
        }
    }


    //工作
    public class Work
    {
        private State current;
        public Work(int wfModel)
        {
            switch (wfModel)
            {
                case 1: current = new wf1(); break;
                case 2: current = new wf2(); break;
            }
        }

        private Dictionary<int, int> stepList = new Dictionary<int, int>();
        /// <summary>
        /// 步骤，状态
        /// </summary>
        public Dictionary<int, int> StepList
        {
            get { return stepList; }
            set { stepList = value; }
        }
        /// <summary>
        /// 是否启用下一个工作流
        /// </summary>
        private bool isStop = false;
        public bool IsStop
        {
            get { return isStop; }
            set { isStop = value; }
        }
        /// <summary>
        /// 当前的步骤
        /// </summary>
        private int currentStep = 0;
        public int CurrentStep
        {
            get { return (currentStep += 1); }
            set { currentStep = value; }
        }
        /// <summary>
        /// 设置当前的工作流实现
        /// </summary>
        /// <param name="s"></param>
        public void SetState(State s)
        {
            current = s;
        }
        /// <summary>
        /// 操作工作流
        /// </summary>
        public void DoWork()
        {
            current.DoWork(this);
        }
    }
}