Unity3D设计模式之命令者模式
发表于2018-07-12
设计模式分很多种，大家或多或少的都有些了解，但真的说到掌握，可能很多人都没什么信心，为此为了加深大家对设计模式的理解，下面就给大家介绍下设计模式中的命令者模式。
命令者模式的定义
“行为请求者”与“行为实现者”通常呈现一种“紧耦合”。但在某些场合，比如要对行为进行“记录、撤销/重做、事务”等处理，这种无法抵御变化的紧耦合是不合适的。在这种情况下，如何将“行为请求者”与“行为实现者”解耦？将一组行为抽象为对象，实现二者之间的松耦合。这就是命令模式。
命令者模式的原理
命令者模式举例—>FSM状态机
首先分析：共同的特性
1.切换到另一种状态时都要先退出当前状态
2.进入要切换的状态
3.每一帧 处理当前的状态涉及的逻辑
接下来上代码
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
//抽象出的父类
public abstract class FSMBase
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protected Animator animator;
public FSMBase(Animator temAnimator)
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animator = temAnimator;
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//进入状态
public abstract void OnEnter();
//当前状态
public abstract void Update();
//离开状态
public abstract void OnLeave();
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//管理类
public class FSMManager
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/// <summary>
/// 当前添加的状态数
/// </summary>
byte currentIndex;
/// <summary>
/// 当前的状态值
/// </summary>
int currentState;
//将所有的动画管理起来
FSMBase[] allState;
/// <summary>
/// count当前动画的数量
/// </summary>
/// <param name="count"></param>
public FSMManager(int count)
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allState = new FSMBase[count];
currentIndex = 0;
currentState = -1;
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/// <summary>
/// 将所有的状态添加到数组
/// </summary>
/// <param name="temBase"></param>
public void AddState(FSMBase temBase)
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if (currentIndex < allState.Length)
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allState[currentIndex] = temBase;
currentIndex++;
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/// <summary>
/// 切换到某一个状态
/// </summary>
/// <param name="index"></param>
public void ChangeState(byte index)
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//判断当前状态是否等于要切换的状态
if (currentState != index)
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if (currentState != -1)
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//退出当前状态
allState[currentState].OnLeave();
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//切换到目标状态
allState[index].OnEnter();
//记录当前状态
currentState = index;
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public void Update()
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if (currentState != -1)
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allState[currentState].Update();
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public class FSM : MonoBehaviour ｛
// Use this for initialization
void Start () ｛
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// Update is called once per frame
void Update () ｛
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using System;
using System.Collections;
using System.Collections.Generic;
using UnityEngine;
public class PlayerIdle : FSMBase
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public PlayerIdle(Animator temAnimator) : base(temAnimator)
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public override void OnEnter()
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animator.SetInteger("StateIndex", 0);
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public override void OnLeave()
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public override void Update()
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public class PlayerWalk : FSMBase
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public PlayerWalk(Animator temAnimator) : base(temAnimator)
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public override void OnEnter()
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animator.SetInteger("StateIndex", 1);
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public override void OnLeave()
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public override void Update()
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public class PlayerRun : FSMBase
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public PlayerRun(Animator temAnimator) : base(temAnimator)
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public override void OnEnter()
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animator.SetInteger("StateIndex", 2);
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public override void OnLeave()
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public override void Update()
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public class PlayerAttack : FSMBase
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public PlayerAttack(Animator temAnimator) : base(temAnimator)
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public override void OnEnter()
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animator.SetInteger("StateIndex", 3);
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public override void OnLeave()
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public override void Update()
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public class PlayerAnimation0 : MonoBehaviour ｛
FSMManager animatorManager;
public enum AnimatorState
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Idle,
Walk,
Run,
Attack,
MaxValue
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// Use this for initialization
void Start () ｛
animatorManager = new FSMManager((int)AnimatorState.MaxValue);
Animator ani = gameObject.GetComponent<Animator>();
PlayerIdle idle = new PlayerIdle(ani);
animatorManager.AddState(idle);
PlayerWalk walk = new PlayerWalk(ani);
animatorManager.AddState(walk);
PlayerRun run = new PlayerRun(ani);
animatorManager.AddState(run);
PlayerAttack attack = new PlayerAttack(ani);
animatorManager.AddState(attack);
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// Update is called once per frame
void Update () ｛
if (Input.GetKeyDown(KeyCode.A))
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ChangeState((int)AnimatorState.Attack);
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public void ChangeState(byte index)
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animatorManager.ChangeState(index);
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优点
1.两个状态之间的耦合性比较低
2.可扩展性比较强
来自：https://blog.csdn.net/battletiger/article/details/78020310