前言

眾所周知，Unity在開發游戲的時候經常用到狀態機，而通常情況下，我們會使用簡單的枚舉類型設置狀態，然后通過調整枚舉，來切換狀態，在簡單情況下是可以的，就像是Unity中Animator切換動畫狀態就是，直接通過動畫片段的名稱切換。而當狀態很多的時候，直接切換就顯得有些很不安全，而且友好性也不是很好，所以根據Unity中Animator這種通過條件切換狀態的架構，我寫了一個簡單的狀態機，給大家分享。

外部委托定義

    /// <summary>

    /// 狀態內部事件委托

    /// </summary>

    public delegate void StateFunctionEventHandler();

    /// <summary>

    /// 狀態條件判斷委托

    /// </summary>

    public delegate bool StateTranslateEventHandler();

狀態類

    /// <summary>

    /// 狀態類

    /// </summary>

    public class State {

        /// <summary>

        /// 狀態內部事件

        /// </summary>

        public event StateFunctionEventHandler stateFunc;

        /// <summary>

        /// 狀態轉換事件<目標狀態,切換條件>

        /// </summary>

        public Dictionary<State,StateTranslateEventHandler> stateTrs;

        /// <summary>

        /// 狀態名稱

        /// </summary>

        /// <value>The name of the state.</value>

        public string stateName{get;private set;}

        /// <summary>

        /// 狀態運行中

        /// </summary>

        public bool isRun = false;

        /// <summary>

        /// 狀態內部事件執行間隔時間（毫秒）

        /// </summary>

        /// <value>The state function delta time.</value>

        public int stateFunctionDeltaTime{private get; set;}

        /// <summary>

        /// 狀態構造

        /// </summary>

        /// <param name="name">Name.</param>

        public State(string name)

        {

            stateName = name;

            stateTrs = new Dictionary<State, StateTranslateEventHandler> ();

            stateFunctionDeltaTime = 200;

            Thread th = new Thread (Update);

            th.Start ();

        }

        /// <summary>

        /// 狀態內部事件執行

        /// </summary>

        public void Update()

        {

            while(true)

            {

                if(!isRun)

                {

                    continue;

                }

                Thread.Sleep (stateFunctionDeltaTime);

                if(stateFunc != null)

                {

                    stateFunc();

                }

            }

        }

        /// <summary>

        /// 注冊切換事件.

        /// </summary>

        /// <param name="target">目標狀態.</param>

        /// <param name="conditional">條件事件.</param>

        public void RegisterTranslate(State target, StateTranslateEventHandler conditional)

        {

            try

            {

                stateTrs.Add (target, conditional);

            }

            catch(Exception ex)

            {

                Debug.LogError(ex.ToString());

            }

        }

    }

狀態管理類

    /// <summary>

    /// 狀態管理

    /// </summary>

    public class StateController : State {

        /// <summary>

        /// 狀態管理構造

        /// </summary>

        /// <param name="name">Name.</param>

        public StateController(string name) : base(name)

        {

            states = new Dictionary<string, State> ();

            stateparams = new Dictionary<string, object> ();

            stateFunc += CheckTranslate;

            isRun = true;

            Thread mainTh = new Thread (Update);

            mainTh.Start ();

        }

        /// <summary>

        /// 狀態字典

        /// </summary>

        Dictionary<string,State> states;

        /// <summary>

        /// 狀態切換參數字典

        /// </summary>

        Dictionary<string,object> stateparams;

        /// <summary>

        /// 當前狀態

        /// </summary>

        public State currentState;

        /// <summary>

        /// 添加狀態

        /// </summary>

        /// <returns>The state.</returns>

        /// <param name="statename">狀態名稱.</param>

        public State AddState(string statename)

        {

            State temp = new State (statename);

            states.Add (statename, temp);

            SetDefault (temp);

            return temp;

        }

        /// <summary>

        /// 添加狀態

        /// </summary>

        /// <param name="s">狀態.</param>

        public void AddState(State s)

        {

            states.Add (s.stateName, s);

            SetDefault (s);

        }

        /// <summary>

        /// 移除狀態

        /// </summary>

        /// <param name="statename">狀態名稱.</param>

        public void RemoveState(string statename)

        {

            states.Remove (statename);

        }

        /// <summary>

        /// 設置默認狀態

        /// </summary>

        /// <param name="s">S.</param>

        private void SetDefault (State s)

        {

            if(states.Count == 1)

            {

                currentState = s;

                s.isRun = true;

            }

        }

        /// <summary>

        /// 切換狀態

        /// </summary>

        /// <param name="name">狀態名稱.</param>

        public void TranslateState(string name)

        {

            if(states[name] != null)

            {

                currentState.isRun = false;

                currentState = states [name];

                states [name].isRun = true;

            }

        }

        /// <summary>

        /// 獲取狀態

        /// </summary>

        /// <returns>The state.</returns>

        /// <param name="statename">Statename.</param>

        public State GetState(string statename)

        {

            return states [statename];

        }

        /// <summary>

        /// 注冊參數

        /// </summary>

        /// <param name="paramName">參數名稱.</param>

        /// <param name="value">參數值.</param>

        public void RegisterParams(string paramName, int value)

        {

            stateparams.Add (paramName, value);

        }

        /// <summary>

        /// 注冊參數

        /// </summary>

        /// <param name="paramName">參數名稱.</param>

        /// <param name="value">參數值.</param>

        public void RegisterParams(string paramName, float value)

        {

            stateparams.Add (paramName, value);

        }

        /// <summary>

        /// 注冊參數

        /// </summary>

        /// <param name="paramName">參數名稱.</param>

        /// <param name="value">參數值.</param>

        public void RegisterParams(string paramName, string value)

        {

            stateparams.Add (paramName, value);

        }

        /// <summary>

        /// 獲取int類型參數

        /// </summary>

        /// <returns>The int parameters.</returns>

        /// <param name="paraName">Para name.</param>

        public int GetIntParams(string paraName)

        {

            return (int)stateparams [paraName];

        }

        /// <summary>

        /// 獲取float類型參數

        /// </summary>

        /// <returns>The float parameters.</returns>

        /// <param name="paraName">Para name.</param>

        public float GetFloatParams(string paraName)

        {

            return (float)stateparams [paraName];

        }

        /// <summary>

        /// 獲取string類型參數

        /// </summary>

        /// <returns>The string parameters.</returns>

        /// <param name="paraName">Para name.</param>

        public string GetStringParams(string paraName)

        {

            return (string)stateparams [paraName];

        }

        /// <summary>

        /// 設置int參數

        /// </summary>

        /// <param name="paraName">Para name.</param>

        /// <param name="value">Value.</param>

        public void SetIntParams(string paraName, int value)

        {

            stateparams[paraName] =value;

        }

        /// <summary>

        /// 設置float參數

        /// </summary>

        /// <param name="paraName">Para name.</param>

        /// <param name="value">Value.</param>

        public void SetFloatParams(string paraName, float value)

        {

            stateparams[paraName] =value;

        }

        /// <summary>

        /// 設置string參數

        /// </summary>

        /// <param name="paraName">Para name.</param>

        /// <param name="value">Value.</param>

        public void SetStringParams(string paraName, string value)

        {

            stateparams[paraName] =value;

        }

        /// <summary>

        /// 檢查狀態切換

        /// </summary>

        private void CheckTranslate()

        {

            foreach (var item in currentState.stateTrs) 

            {

                if(item.Value())

                {

                    TranslateState(item.Key.stateName);

                }

            }

        }

    }

實例應用

public class GameController : MonoBehaviour {

    //單例

    static StateController stateController;

    //外部測試

    public bool test = false;

    void Awake()

    {

        //1、實例化單例

        stateController = new StateController ("MainSc");

    }

    void Start()

    {

        //2、注冊狀態Idle

        State idle = stateController.AddState ("Idle");

        //2、注冊狀態Run

        State run = stateController.AddState ("Run");

        //3、注冊參數Speed,默認值0

        stateController.RegisterParams ("Speed", 0f);

        //4、idle內部事件

        idle.stateFunc += () => {

            Debug.Log(idle.stateName);

        };

        //4、run內部事件

        run.stateFunc += () => {

            Debug.Log(run.stateName);

        };

        //5、切換事件Idle --> Run

        idle.RegisterTranslate (run, () => {

            if(stateController.GetFloatParams("Speed") > 0.5f)

            {

                return true;

            }

            return false;

        });

        //5、切換事件Run --> Idle

        run.RegisterTranslate (idle, () => {

            if(stateController.GetFloatParams("Speed") <= 0.5f)

            {

                return true;

            }

            return false;

        });

    }

    void Update()

    {

        if (test)

        {

            //6、切換參數，調整狀態

            stateController.SetFloatParams("Speed",1);

        }

        else

        {

            stateController.SetFloatParams("Speed",0);

        }

    }

}

結束語

這個工具類中用到了多線程的處理，其中各個狀態的線程是持續執行的，所以后期還會繼續改進，如果讀者朋友有哪些更好的建議和意見，歡迎評論。