状态模式
介绍
设计模式 | 定义 | 案例 | 问题堆积在哪里 | 解决办法 |
状态模式 | 一个对象 状态可以发生改变 不同的状态又有不同的行为逻辑 | 游戏角色 加载不同的技能 每个技能有不同的:攻击逻辑 攻击范围 动作等等 | 1 状态很多 2 每个状态有自己的属性和逻辑 | 每种状态单独写一个类 角色需要那个状态就加载哪一个 |
类图
角色:
stateBase 抽象状态
stateA 具体状态A
stateB 具体状态B
stateC 具体状态C
FactoryState 状态工厂
代码
RoleContext
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class RoleContext
{string name;StateBase currentState = null;public RoleContext(){name = "独孤求败";}// 展示动作public void ShowAction(){if (null != currentState){currentState.Action();}}// 切换状态public void ChangeActionState(StateBase newState){currentState = newState;}
}
StateBase
public abstract class StateBase
{public abstract void Action();
}
StateA
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class StateA : StateBase
{string name = "普攻";public override void Action(){Debug.Log("释放-" + name);}
}
StateB
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class StateB : StateBase
{string name = "次元斩";public override void Action(){Debug.Log("释放-" + name);}
}
StateC
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class StateC:StateBase
{string name = "升龙击";public override void Action(){Debug.Log("释放-" + name);}
}
FactoryState
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class FactoryState
{// 单例static FactoryState self = null;FactoryState() { }public static FactoryState Instance(){if (null == self)self = new FactoryState();return self;}Dictionary<string, StateBase> dic = new Dictionary<string, StateBase>();// 获取实例public StateBase GetStateIns(string className){StateBase ins = null;switch (className){case "StateA":{if (false == dic.ContainsKey(className))ins = new StateA();elseins = dic[className];}break;case "StateB":{if (false == dic.ContainsKey(className))ins = new StateB();elseins = dic[className];}break;case "StateC":{if (false == dic.ContainsKey(className))ins = new StateC();elseins = dic[className];}break;default:Debug.Log("未发现该类!");break;}return ins;}
}
测试代码
using System.Collections;
using System.Collections.Generic;
using UnityEngine;public class TestZT : MonoBehaviour
{void Start(){RoleContext role = new RoleContext();// 切换技能Arole.ChangeActionState(FactoryState.Instance().GetStateIns("StateA"));role.ShowAction();// 切换技能Brole.ChangeActionState(FactoryState.Instance().GetStateIns("StateB"));role.ShowAction();// 切换技能Crole.ChangeActionState(FactoryState.Instance().GetStateIns("StateC"));role.ShowAction();}}
结果
总结
状态模式
1 是一个非常好用的 解耦合的手段, 角色不同的状态封装不同的(动作,属性,限制)
2 非常符合对修改封闭对扩展开发的原则。
3 让状态的职责更加的单一
4 也符合了依赖倒置 ,依赖了抽象
5 符合了迪米特原则,角色对状态类内部的具体实现不知道