构建状态机 [英] Building a state machine

问题描述

我正在为项目创建状态机。该项目将有许多算法，每个算法都有一个状态机。返回下一个状态的枚举会污染基类枚举，所以不是真的很激动。



下面是我提出的工作代码。对于返回类型的对象并不是很疯狂但是没有真正看到它的方法。



任何人都有任何想法？



我尝试过：

I'm looking at creating a state machine for a project. The project will have many algorithms each having a state machine in it. Returning an enumeration for the next state would pollute a base class enumeration, so not really thrilled about that.

Below is working code that I came up with. Not crazy about the return type of object but don't really see a way around it.

Anyone have any thoughts?

What I have tried:

using System;

namespace StateMachine
{
	/// 
	public class StateMachine2BaseClass
	{
		protected void RunAlgorithm(Func<object> nextState)
		{
			while (nextState != null)
			{
				var currentState = nextState;
				nextState = (Func<object>)currentState();
			}
		}

		protected Func<object> End()
		{
			return null;
		}
	}

	/// 
	public class StateMachine2 : StateMachine2BaseClass
	{
		private int count;

		public void Run()
		{
			RunAlgorithm(Start);
		}

		private Func<object> Start()
		{
			Console.WriteLine("Start");
			return Step_1;
		}

		private Func<object> Step_1()
		{
			if (++count > 5)
				return Step_2;

			Console.WriteLine("Step 1");

			return Step_1;
		}

		private Func<object> Step_2()
		{
			Console.WriteLine("Step 2");
			return End;
		}
	}
}

推荐答案

正如F-ES Sitecore建议的那样，基于类方法可以更好地工作。

定义一个抽象的State类，它声明一个抽象的DoWork方法，将机器信息类作为参数，描述状态将运行的信息，如果有的话，并返回一个状态实例。



然后，对于您需要的每个状态，定义一个从State类派生的新类，并为每个实现DoWork方法。



所有你要做的就是：

As F-ES Sitecore suggests, a class - based approach would work better.
Define an abstract State class which declares an abstract DoWork method, taking as a parameter the "machine info" class which describes the information the states will operate on, if any and returning a State instance.

Then for each state you need, define a new class derived from the State class and implement the DoWork method for each.

All you have to do then is:

protected void RunAlgorithm(Func<object> nextState)
    {
    State currentState = new FirstState();
    while (currentState != null)
        {
        currentState = currentState.DoWork(machineInfo);
        }
    }

系统将整理出每次需要调用的DoWork方法。

The system will sort out which DoWork method it needs to call each time.

这篇关于构建状态机的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！