如何将观察者模式的消息发布与订阅机制改写为支持长尾词的通用？

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观察者模式：当对象之间存在一对多关系时，使用观察者模式。例如，当一个对象被修改时，会自动通知依赖它的对象。这属于行为型模式。主要解决：一个对象状态的变化需要同时改变其他对象的状态。

观察者模式：当对象间存在一对多关系时，则使用观察者模式。比如，当一个对象被修改时，则会自动通知依赖它的对象。观察者模式属于行为型模式。
主要解决：一个对象状态改变给其他对象通知的问题，而且要考虑到易用和低耦合，保证高度的协作。

TestCommonEvent.cs

1 using System.Collections.Generic; 2 3 public class TestCommonEvent : System.IDisposable 4 { 5 public delegate void OnActionHandler(object obj); 6 public Dictionary<ushort, LinkedList<OnActionHandler>> dic = new Dictionary<ushort, LinkedList<OnActionHandler>>(); 7 8 /// <summary> 9 /// 添加监听 10 /// </summary> 11 /// <param name="key"></param> 12 /// <param name="actionEvent"></param> 13 public void AddEventListener(ushort key, OnActionHandler actionEvent) 14 { 15 dic.TryGetValue(key, out LinkedList<OnActionHandler> list); 16 if (list == null) 17 { 18 list = new LinkedList<OnActionHandler>(); 19 dic[key] = list; 20 } 21 list.AddLast(actionEvent); 22 } 23 24 /// <summary> 25 /// 移除监听 26 /// </summary> 27 /// <param name="key"></param> 28 /// <param name="actionEvent"></param> 29 public void RemoveEventListener(ushort key, OnActionHandler actionEvent) 30 { 31 if (dic.TryGetValue(key, out LinkedList<OnActionHandler> list)) 32 { 33 list.Remove(actionEvent); 34 if (list.Count == 0) 35 { 36 dic.Remove(key); 37 } 38 } 39 } 40 41 /// <summary> 42 /// 派发 43 /// </summary> 44 /// <param name="key"></param> 45 /// <param name="obj"></param> 46 public void Dispatch(ushort key, object obj) 47 { 48 if (dic.TryGetValue(key, out LinkedList<OnActionHandler> list)) 49 { 50 for (var v = list.First; v != null; v = v.Next) 51 { 52 v.Value?.Invoke(obj); 53 } 54 } 55 } 56 57 public void Dispose() 58 { 59 dic.Clear(); 60 } 61 }

TestEventManager.cs

1 public class TestEventManager : System.IDisposable 2 { 3 public TestCommonEvent commonEvent; 4 public TestEventManager() 5 { 6 commonEvent = new TestCommonEvent(); 7 } 8 9 public void Init() 10 { 11 } 12 13 public void Dispose() 14 { 15 commonEvent.Dispose(); 16 } 17 }

测试用例：

建3个物体 分别挂上对应的脚本：

Xiaozhang.cs

1 using UnityEngine; 2 3 public class Xiaozhang : MonoBehaviour 4 { 5 void Update() 6 { 7 if (Input.GetKeyDown(KeyCode.F)) 8 { 9 string times = "16:30"; 10 if (TestGameEntry.EventMgr != null) 11 { 12 TestGameEntry.EventMgr.commonEvent.Dispatch(TestCommonEventId.xiaozhangFangXue, times); 13 } 14 } 15 } 16 } View Code

Xiaohong.cs

1 using UnityEngine; 2 3 public class Xiaohong : MonoBehaviour 4 { 5 void Start() 6 { 7 if (TestGameEntry.EventMgr != null) 8 { 9 TestGameEntry.EventMgr.commonEvent.AddEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue); 10 } 11 } 12 13 private void Xiaozhangfangxue(object obj) 14 { 15 Debug.LogError("小张放学了,我去找他玩"); 16 } 17 18 private void OnDestroy() 19 { 20 TestGameEntry.EventMgr.commonEvent.RemoveEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue); 21 } 22 } View Code

mama.cs

1 using UnityEngine; 2 3 public class Mama : MonoBehaviour 4 { 5 void Start() 6 { 7 if (TestGameEntry.EventMgr != null) 8 { 9 TestGameEntry.EventMgr.commonEvent.AddEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue); 10 } 11 } 12 private void Xiaozhangfangxue(object obj) 13 { 14 Debug.LogError("小张" + obj.ToString() + "点放学了,我得去接孩子了"); 15 } 16 17 private void OnDestroy() 18 { 19 TestGameEntry.EventMgr.commonEvent.RemoveEventListener(TestCommonEventId.xiaozhangFangXue, Xiaozhangfangxue); 20 } 21 } View Code

TestCommonEventId.cs

public class TestCommonEventId { public const ushort xiaozhangFangXue = 10001; }

按键 ”F“ 进行测试