济南莱芜最新消息东莞网站关键词优化排名

🎮 策略模式（Strategy Pattern）深度解析

——以Unity实现灵活AI行为与动态伤害计算为核心案例

---

一、模式本质与核心价值

核心目标：
✅ 定义算法族，封装每个算法，使它们可互换
✅ 运行时动态切换算法，避免使用多重条件判断
✅ 符合开闭原则，易于扩展新算法

关键术语：

• Strategy（策略接口）：定义算法族的通用接口
• ConcreteStrategy（具体策略）：实现具体算法逻辑
• Context（上下文）：持有策略引用，负责调用算法

数学表达：
设算法集合S = {s₁, s₂, …, sₙ}，上下文C满足：
C.Algorithm = sᵢ → C.Execute() = sᵢ.Process()

---

二、经典UML结构

---

三、Unity实战代码（动态伤害计算系统）

1. 定义策略接口与上下文

public interface IDamageStrategy {float CalculateDamage(Character attacker, Character target);
}public class Weapon : MonoBehaviour {private IDamageStrategy _damageStrategy;public void SetStrategy(IDamageStrategy strategy) {_damageStrategy = strategy;}public void Attack(Character attacker, Character target) {float damage = _damageStrategy.CalculateDamage(attacker, target);target.TakeDamage(damage);}
}

2. 实现具体策略

// 物理伤害策略
public class PhysicalDamage : IDamageStrategy {public float CalculateDamage(Character attacker, Character target) {return attacker.Strength * 2 - target.Defense;}
}// 魔法伤害策略
public class MagicDamage : IDamageStrategy {public float CalculateDamage(Character attacker, Character target) {return attacker.Intelligence * 3 - target.MagicResist;}
}// 暴击伤害策略
public class CriticalStrike : IDamageStrategy {[SerializeField] private float _critChance = 0.3f;public float CalculateDamage(Character attacker, Character target) {float baseDamage = attacker.Strength * 1.5f;return Random.value < _critChance ? baseDamage * 2 : baseDamage;}
}

3. 客户端使用

public class PlayerCombat : MonoBehaviour {[SerializeField] private Weapon _sword;void Update() {if(Input.GetKeyDown(KeyCode.Alpha1)) {_sword.SetStrategy(new PhysicalDamage());}if(Input.GetKeyDown(KeyCode.Alpha2)) {_sword.SetStrategy(new MagicDamage());}if(Input.GetMouseButtonDown(0)) {Character enemy = GetTargetEnemy();_sword.Attack(GetComponent<Character>(), enemy);}}
}

---

四、模式进阶技巧

1. 策略组合

public class CompositeStrategy : IDamageStrategy {private List<IDamageStrategy> _strategies = new();public void AddStrategy(IDamageStrategy strategy) {_strategies.Add(strategy);}public float CalculateDamage(Character attacker, Character target) {return _strategies.Sum(s => s.CalculateDamage(attacker, target));}
}

2. 策略工厂

public class DamageStrategyFactory {public IDamageStrategy Create(WeaponType type) {return type switch {WeaponType.Sword => new PhysicalDamage(),WeaponType.Staff => new MagicDamage(),WeaponType.Dagger => new CriticalStrike(),_ => throw new ArgumentException()};}
}

3. 数据驱动策略

[CreateAssetMenu]
public class DamageConfig : ScriptableObject {public AnimationCurve DamageCurve;public GameObject ImpactEffect;
}public class ConfigurableDamage : IDamageStrategy {private DamageConfig _config;public float CalculateDamage(Character attacker, Character target) {float levelFactor = _config.DamageCurve.Evaluate(attacker.Level);return attacker.BaseDamage * levelFactor;}
}

---

五、游戏开发典型应用场景

1. AI行为系统

   public class NPCController {private IMovementStrategy _movementStrategy;public void SetMovementStrategy(IMovementStrategy strategy) {_movementStrategy = strategy;}void Update() {_movementStrategy.Move(transform);}
   }
   

2. 技能效果系统

   public class SkillSystem {private ISkillEffect _effect;public void CastSkill() {_effect.ApplyEffect(target);}
   }
   

3. 成就解锁条件

   public class AchievementCondition {private IUnlockStrategy _strategy;public bool CheckUnlock(Player player) {return _strategy.IsUnlocked(player);}
   }
   

4. 物理材质系统

   public class SurfaceResponse {private IBounceStrategy _bounceStrategy;public Vector3 CalculateBounce(Vector3 input) {return _bounceStrategy.CalculateBounce(input);}
   }
   

---

六、性能优化策略

策略	实现方式	适用场景
策略缓存	对象池管理策略实例	高频策略切换
预编译策略	使用C#委托或表达式树	高性能计算场景
数据导向设计	策略参数结构体化	大量相似策略
异步加载	按需加载策略资源	复杂策略配置

---

七、模式对比与选择

维度	策略模式	状态模式
关注点	算法实现	状态转换
切换机制	主动切换	自动转换
对象关系	平行策略	状态链
典型应用	伤害计算	AI状态机

---

八、最佳实践原则

1. 接口最小化：策略接口保持单一职责
2. 无状态策略：尽量设计无状态的策略类
3. 防御性编程：

   public void SetStrategy(IDamageStrategy strategy) {_damageStrategy = strategy ?? throw new ArgumentNullException();
   }
   

4. 策略验证：

   public bool IsStrategyValid() {return _damageStrategy != null && _damageStrategy.IsAvailable();
   }
   

---

九、常见问题解决方案

Q1：如何处理策略间共享数据？
→ 使用上下文传递参数

public interface IStrategy {void Execute(SharedData context);
}public class SharedData {public Character Attacker;public Character Target;public float EnvironmentFactor;
}

Q2：如何实现跨策略配置？
→ 使用策略配置中心

public class StrategyConfig : MonoBehaviour {[SerializeField] private StrategyMapping[] _mappings;public IStrategy GetStrategy(string key) {return _mappings.FirstOrDefault(m => m.Key == key)?.Strategy;}
}[System.Serializable]
public class StrategyMapping {public string Key;public IStrategy Strategy;
}

Q3：如何调试策略执行流程？
→ 实现策略日志代理

public class LoggingStrategyProxy : IStrategy {private IStrategy _wrapped;public void Execute() {Debug.Log($"开始执行策略：{_wrapped.GetType().Name}");_wrapped.Execute();Debug.Log("策略执行完成");}
}

---

上一篇 【行为型之状态模式】深度剖析——Unity角色行为控制与AI决策的终极解决方案
下一篇 【行为型之模板方法模式】游戏开发实战——Unity标准化流程与可扩展架构的核心实现