技術標籤：UnityC#基礎

using System;
using System.Collections.Generic;
using FrameWork;
using UnityEngine;

public abstract class StateSystem<T> : MonoBehaviour
{
    /// <summary>
    /// 狀態機
    /// </summary>
    protected StateMachine<T> mState;

    /// <summary>
    /// 狀態棧（可用於返回使用）
    /// </summary>
 

    protected Stack<T> mStateStack;

    private void Awake()
    {
        mState = new StateMachine<T>();
        mStateStack = new Stack<T>();

        initialize();
        initStates();
    }

    protected virtual void initialize()
    {
    }

    protected virtual void initStates
 
()
    {
    }

    public void OnEnable()
    {
        mState.OnStart();
    }

    public virtual void Update()
    {
        mState.OnUpdate();
    }

    public void OnDisable()
    {
        mState.OnStop();
    }

    /// <summary>
    /// 切換狀態
    /// </summary>
    /// <param name="state">欲切換的狀態</param>
 

    /// <param name="saveState">是否儲存上一個狀態</param>
    public void ChangeState(T state, bool saveState = false)
    {
        try
        {
            if (mState.CurrentState.Equals(state))
            {
                return;
            }

            if (saveState)
            {
                mStateStack.Push(mState.CurrentState);
            }

            Debug.LogFormat("切換狀態：{0} -> {1}", mState.CurrentState, state);
            mState.ChangeState(state);
        }
        catch (Exception e)
        {
            Debug.Log(e.Message);
            throw;
        }
    }

    /// <summary>
    /// 當前狀態
    /// </summary>
    public T currentState
    {
        get { return mState.CurrentState; }
    }

    /// <summary>
    /// 返回到上一個儲存的狀態
    /// </summary>
    /// <returns></returns>
    public bool BackState()
    {
        if (mStateStack.Count == 0)
        {
            return false;
        }

        T lastState = mStateStack.Pop();
        mStateStack.Clear();
        ChangeState(lastState);
        return true;
    }
}

using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
using UnityEngine.XR;

namespace FrameWork
{
    public class StateMachine<T>
    {
        private class State
        {
            public readonly T label;
            public readonly Action onStart;
            public readonly Func<T> onUpdate;
            public readonly Action onStop;

            public State(T label, Action onStart, Func<T> onUpdate, Action onStop)
            {
                this.label = label;
                this.onStart = onStart;
                this.onUpdate = onUpdate;
                this.onStop = onStop;
            }
        }

        /// <summary>
        /// 狀態集合
        /// </summary>
        private readonly Dictionary<T, State> mStateDictionary;

        private State mCurrentState;

        /// <summary>
        /// 上一個狀態
        /// </summary>
        private State mPreState;

        /// <summary>
        /// 進入的狀態名稱
        /// </summary>
        private T mEnterState;

        /// <summary>
        /// 當前狀態的label
        /// </summary>
        public T CurrentState
        {
            get { return mCurrentState.label; }
            set { ChangeState(value); }
        }

        /// <summary>
        /// 返回上一狀態label
        /// </summary>
        public T PreState => mPreState.label;

        public bool IsRunning
        {
            get { return CurrentState != null; }
        }

        public StateMachine()
        {
            mStateDictionary = new Dictionary<T, State>();
        }

        public void OnStart()
        {
            if (mStateDictionary.Count == 0)
            {
                return;
            }

            mCurrentState = mStateDictionary[mEnterState];
            if (mCurrentState != null && mCurrentState.onStart != null)
            {
                mCurrentState.onStart();
            }
        }

        public void OnUpdate()
        {
            if (mCurrentState != null && mCurrentState.onUpdate != null)
            {
                mCurrentState.onUpdate();
            }
        }

        public void OnStop()
        {
            if (mCurrentState != null && mCurrentState.onStop != null)
            {
                mCurrentState.onStop();
            }
        }

        /// <summary>
        /// 新增狀態
        /// </summary>
        /// <param name="label">狀態</param>
        /// <param name="onStart">在狀態開始時呼叫</param>
        /// <param name="onUpdate">在狀態期間持續呼叫</param>
        /// <param name="onStop">在狀態結束時呼叫</param>
        public void AddState(T label, Action onStart, Func<T> onUpdate, Action onStop)
        {
            State state = new State(label, onStart, onUpdate, onStop);
            mStateDictionary[label] = state;
            if (mCurrentState == null) //第一個新增的狀態為初始狀態
            {
                mCurrentState = state;
                mEnterState = mCurrentState.label;
            }
        }


        /// <summary>
        /// 切換狀態
        /// </summary>
        /// <param name="newLabel"></param>
        public void ChangeState(T newLabel)
        {
            if (mCurrentState != null && mCurrentState.onStop != null)
            {
                mCurrentState.onStop();
            }

            mPreState = mCurrentState;
            mCurrentState = mStateDictionary[newLabel];

            if (mCurrentState != null && mCurrentState.onStart != null)
            {
                mCurrentState.onStart();
            }
        }
    }
}