Question

我目前正在开发一款小型游戏引擎，而且我有点想找到合适的模式。首先是一些代码片段，以了解我想要实现的目标：

单位：能力施法者/目标（投掷能力或接受能力）

public class Unit
{

 public string Name { get; set; } // Unit name

 public List<BaseAbility> MyAbilities{get; set;} // abilities that an unit has.

}

能力：

public abstract class BaseAbility
{
    public string Name {get; set;} // ability name

    public Unit Caster { get; set; } // ability caster (owner)

    public List<BaseEffect> EffectList {get; set;} // effects that an ability possess

    // apply all effects that this ability has on the selected target
    public virtual void DoAbility(Unit target) 
    {
        foreach (BaseEffect eff in this.EffectList)
        {                
            eff.CalculateEffect(target);
        }
    }

    // here we gonna subscribe to some events 
    public abstract void initListeners();

}

效果：

 public abstract class BaseEffect
 {
   public BaseAbility Owner { get; set; } // each effect belong to an ability

   protected string Name { get; set; } // effect name

   public EventDispatcher Event { get; set; } // the event to dispatched when this effect is called or used

   //apply effect on target
   public virtual void CalculateEffect(Unit target) 
   {
     // Do Stuffs here like damage and poison etc etc
     this.Event.DispatchMyEvent();
   }
}

事件调度程序：

public class EventDispatcher
{
  private object mySender;
  private EffectEventArgs myArgument;

  public delegate void EventHandler(object sender, EffectEventArgs argument);
  public event EventHandler OnMyEvent;

  public EventDispatcher(object sender, EffectEventArgs argument)
  {
    this.mySender = sender;
    this.myArgument = argument;
  }

  public void DispatchMyEvent() 
  {
    if (OnMyEvent != null)
    {
        OnMyEvent(this.mySender, this.myArgument);
        Debug.WriteLine("event has been raised");
    }
  }
}

效果事件参数：

 public class EffectEventArgs : EventArgs
 {
   private Unit target; // target affected by effect

   // not sure if we even need this EffectEventArgs ?!
   public EffectEventArgs(Unit unit) 
   {
    this.target = unit;
   }
 }

现在我将为模拟创建2个效果和2个技能以及2个单位：

火焰效果：

  public class FireEffect : BaseEffect
  {
    public FireEffect(BaseAbility effectOwner)
    {
     this.Owner = effectOwner;
     this.Name = "Fire";
    }

    public override void CalculateEffect(Unit target)
    {
      // set the event here (to get the target as argument for the event)
      this.Event = new EventDispatcher(this.Owner, new EffectEventArgs(target));
      base.CalculateEffect(target);
    } 
  }

风效果：与火焰效果相同，但名称和事件不同，也适用不同的效果。

火球能力：

 public class FireBall : BaseAbility
 {
   public FireBall(Unit caster)
   {
    this.Name = "FireBall";
    this.Caster = caster;
    this.EffectList = new List<BaseEffect>();
    this.EffectList.Add(new FireEffect(this)); // fire ball ability has "FireEffect" as effect
   }

   public override void DoEffect(Unit target)
   {
    base.DoEffect(target);
   }
 }

两个单位，让我们说： “龙”作为单位=＆gt;有FireBall（能力）并且会击中=＆gt; “少林风之师”作为单位有一个被称为“WindFury”的被动行为

WindFury：

  public class PassiveAbility : BaseAbility
  {
    public PassiveAbility(Unit caster)  
    {
     this.Name = "WindFury";
     this.Caster = caster;
     this.EffectList = new List<BaseEffect>();
     this.EffectList.Add(new WindEffect(this));
     this.initListeners(); // subscribe to events (aka add listeners)
    }

    public override void DoEffect(Unit target)
    {
      base.DoEffect(target);
    }

    // THE MAIN PROBLEM : 
    public override void initListeners() 
    {

     // here i need to subscribe to an event fired from any Instance/Object of type FireEffect so that the targeted Unit 
     // can react to the Unit caster (kind of counter attack)
     // to resume this , it should follows this logic :
     // if any Ability has The effect(FireEffect => FireBall for example) was casted 
     // on this Unit thats possess this passive, react to it and counter with (WindEffect)
     // otherwise put : when our dragon or Ryu or even Sasuke throw an ability with
     // a FireEffect on our friend "Shaolin" ,he should react to it
     // and send the attacker flying with a powerfull WindEffect 
    }

    public void CallBack(object sender, EffectEventArgs e) 
    {
     BaseAbility ab = (BaseAbility)sender;
     this.DoEffect(ab.UnitCaster); // hit the unit caster back (revenge)
    }
 }

请注意，我们可以在这个游戏或模拟中拥有这么多龙和Shaolins，任何被动持有者（单位）都应该只对攻击者（单位）等作出反应。

编辑:(回顾主要问题）

如何订阅通过 PassiveAbility.initListeners（）从事件从任何类型的FireEffect 触发事件（使用fireEffect的能力）???

非常感谢您的支持和贡献。

Youness

Answer 1

将静态EventDispatcher添加到FireEffect并订阅。

public class FireEffect : BaseEffect
{
    public static EventDispatcher FireEffectEventDispatcher = new EventDispatcher(null,null);

    public FireEffect(BaseAbility effectOwner)
    {
        this.Owner = effectOwner;
        this.Name = "Fire";
    }

    public override void CalculateEffect(Unit target)
    {
        // set the event here (to get the target as argument for the event)
        FireEffectEventDispatcher.mySender = Owner;
        FireEffectEventDispatcher.myArgument = new EffectEventArgs(target);
        // Fire the event
        FireEffectEventDispatcher.DispatchMyEvent();
        //If you still want the base effect firing.
        base.CalculateEffect(target);
    } 
}

为了完成这项工作，您还需要更改EventDispatcher，以便在构建后设置发件人/参数（无论如何都无法理解 - 它＆＃ 39;无用的限制）。

但我建议您重做（或删除）EventDispatcher实施。在事件触发期间更合理地设置事件参数时，在构造函数中设置事件参数是没有意义的。

如何订阅从X类型的任何实例/对象触发的事件

1 个答案: