Advanced CSharp Messenger 属于C#事件的一种。 维基百科中由详细的说明 

Advanced CSharp Messenger的特点可以将游戏对象做为参数发送。到底Advanced CSharp Messenger有什么用呢？先创建一个立方体对象，然后把Script脚本绑定在这个对象中。脚本中有一个方法叫DoSomething()。写一段简单的代码，通常我们在调用方法的时候需要这样来写。

private Script script;    void Awake()    {        GameObject cube = GameObject.Find("Cube");        script = cube.GetComponent

 

代码比较简单，我就不注释了。 原理就是先获取游戏对象，接着获取脚本组件对象，最后通过脚本组件对象去调用对应脚本中的方法，这样的调用方法我们称之为直接调用。

这个例子中我只调用了一个对象的方法，如果说有成千上万个对象，那么这样调用是不是感觉自己的代码非常的丑？因为你需要一个一个的获取对象然后获取脚本组件然后在调用方法。。。。。 （想想都恐怖！！）

下面我们在用Advanced CSharp Messenger来实现事件的调用。按照维基百科中首先把Message.cs 和Callback.cs拷贝在你的工程中。

CallBack.cs

public delegate void Callback();public delegate void Callback
     
      (T arg1);public delegate void Callback
      
       (T arg1, U arg2);public delegate void Callback
       
        (T arg1, U arg2, V arg3);
       
      
     

Message.cs

/* * Advanced C# messenger by Ilya Suzdalnitski. V1.0 *  * Based on Rod Hyde's "CSharpMessenger" and Magnus Wolffelt's "CSharpMessenger Extended". *  * Features:     * Prevents a MissingReferenceException because of a reference to a destroyed message handler.     * Option to log all messages     * Extensive error detection, preventing silent bugs *  * Usage examples:     1. Messenger.AddListener
     
      ("prop collected", PropCollected);        Messenger.Broadcast
      
       ("prop collected", prop);     2. Messenger.AddListener
       
        ("speed changed", SpeedChanged);        Messenger.Broadcast
        
         ("speed changed", 0.5f); *  * Messenger cleans up its evenTable automatically upon loading of a new level. *  * Don't forget that the messages that should survive the cleanup, should be marked with Messenger.MarkAsPermanent(string) *  */ //#define LOG_ALL_MESSAGES//#define LOG_ADD_LISTENER//#define LOG_BROADCAST_MESSAGE#define REQUIRE_LISTENER using System;using System.Collections.Generic;using UnityEngine; static internal class Messenger {    #region Internal variables     //Disable the unused variable warning#pragma warning disable 0414    //Ensures that the MessengerHelper will be created automatically upon start of the game.    static private MessengerHelper messengerHelper = ( new GameObject("MessengerHelper") ).AddComponent< MessengerHelper >();#pragma warning restore 0414     static public Dictionary
         
           eventTable = new Dictionary
          
           (); //Message handlers that should never be removed, regardless of calling Cleanup static public List< string > permanentMessages = new List< string > (); #endregion #region Helper methods //Marks a certain message as permanent. static public void MarkAsPermanent(string eventType) {#if LOG_ALL_MESSAGES Debug.Log("Messenger MarkAsPermanent \t\"" + eventType + "\"");#endif permanentMessages.Add( eventType ); } static public void Cleanup() {#if LOG_ALL_MESSAGES Debug.Log("MESSENGER Cleanup. Make sure that none of necessary listeners are removed.");#endif List< string > messagesToRemove = new List
           
            (); foreach (KeyValuePair
            
              pair in eventTable) { bool wasFound = false; foreach (string message in permanentMessages) { if (pair.Key == message) { wasFound = true; break; } } if (!wasFound) messagesToRemove.Add( pair.Key ); } foreach (string message in messagesToRemove) { eventTable.Remove( message ); } } static public void PrintEventTable() { Debug.Log("\t\t\t=== MESSENGER PrintEventTable ==="); foreach (KeyValuePair
             
               pair in eventTable) { Debug.Log("\t\t\t" + pair.Key + "\t\t" + pair.Value); } Debug.Log("\n"); } #endregion #region Message logging and exception throwing static public void OnListenerAdding(string eventType, Delegate listenerBeingAdded) {#if LOG_ALL_MESSAGES || LOG_ADD_LISTENER Debug.Log("MESSENGER OnListenerAdding \t\"" + eventType + "\"\t{ " + listenerBeingAdded.Target + " -> " + listenerBeingAdded.Method + "}");#endif if (!eventTable.ContainsKey(eventType)) { eventTable.Add(eventType, null ); } Delegate d = eventTable[eventType]; if (d != null && d.GetType() != listenerBeingAdded.GetType()) { throw new ListenerException(string.Format("Attempting to add listener with inconsistent signature for event type {0}. Current listeners have type {1} and listener being added has type {2}", eventType, d.GetType().Name, listenerBeingAdded.GetType().Name)); } } static public void OnListenerRemoving(string eventType, Delegate listenerBeingRemoved) {#if LOG_ALL_MESSAGES Debug.Log("MESSENGER OnListenerRemoving \t\"" + eventType + "\"\t{ " + listenerBeingRemoved.Target + " -> " + listenerBeingRemoved.Method + "}");#endif if (eventTable.ContainsKey(eventType)) { Delegate d = eventTable[eventType]; if (d == null) { throw new ListenerException(string.Format("Attempting to remove listener with for event type \"{0}\" but current listener is null.", eventType)); } else if (d.GetType() != listenerBeingRemoved.GetType()) { throw new ListenerException(string.Format("Attempting to remove listener with inconsistent signature for event type {0}. Current listeners have type {1} and listener being removed has type {2}", eventType, d.GetType().Name, listenerBeingRemoved.GetType().Name)); } } else { throw new ListenerException(string.Format("Attempting to remove listener for type \"{0}\" but Messenger doesn't know about this event type.", eventType)); } } static public void OnListenerRemoved(string eventType) { if (eventTable[eventType] == null) { eventTable.Remove(eventType); } } static public void OnBroadcasting(string eventType) {#if REQUIRE_LISTENER if (!eventTable.ContainsKey(eventType)) { throw new BroadcastException(string.Format("Broadcasting message \"{0}\" but no listener found. Try marking the message with Messenger.MarkAsPermanent.", eventType)); }#endif } static public BroadcastException CreateBroadcastSignatureException(string eventType) { return new BroadcastException(string.Format("Broadcasting message \"{0}\" but listeners have a different signature than the broadcaster.", eventType)); } public class BroadcastException : Exception { public BroadcastException(string msg) : base(msg) { } } public class ListenerException : Exception { public ListenerException(string msg) : base(msg) { } } #endregion #region AddListener //No parameters static public void AddListener(string eventType, Callback handler) { OnListenerAdding(eventType, handler); eventTable[eventType] = (Callback)eventTable[eventType] + handler; } //Single parameter static public void AddListener
              
               (string eventType, Callback
               
                 handler) { OnListenerAdding(eventType, handler); eventTable[eventType] = (Callback
                
                 )eventTable[eventType] + handler; } //Two parameters static public void AddListener
                 
                  (string eventType, Callback
                  
                    handler) { OnListenerAdding(eventType, handler); eventTable[eventType] = (Callback
                   
                    )eventTable[eventType] + handler; } //Three parameters static public void AddListener
                    
                     (string eventType, Callback
                     
                       handler) { OnListenerAdding(eventType, handler); eventTable[eventType] = (Callback
                      
                       )eventTable[eventType] + handler; } #endregion #region RemoveListener //No parameters static public void RemoveListener(string eventType, Callback handler) { OnListenerRemoving(eventType, handler); eventTable[eventType] = (Callback)eventTable[eventType] - handler; OnListenerRemoved(eventType); } //Single parameter static public void RemoveListener
                       
                        (string eventType, Callback
                        
                          handler) { OnListenerRemoving(eventType, handler); eventTable[eventType] = (Callback
                         
                          )eventTable[eventType] - handler; OnListenerRemoved(eventType); } //Two parameters static public void RemoveListener
                          
                           (string eventType, Callback
                           
                             handler) { OnListenerRemoving(eventType, handler); eventTable[eventType] = (Callback
                            
                             )eventTable[eventType] - handler; OnListenerRemoved(eventType); } //Three parameters static public void RemoveListener
                             
                              (string eventType, Callback
                              
                                handler) { OnListenerRemoving(eventType, handler); eventTable[eventType] = (Callback
                               
                                )eventTable[eventType] - handler; OnListenerRemoved(eventType); } #endregion #region Broadcast //No parameters static public void Broadcast(string eventType) {#if LOG_ALL_MESSAGES || LOG_BROADCAST_MESSAGE Debug.Log("MESSENGER\t" + System.DateTime.Now.ToString("hh:mm:ss.fff") + "\t\t\tInvoking \t\"" + eventType + "\"");#endif OnBroadcasting(eventType); Delegate d; if (eventTable.TryGetValue(eventType, out d)) { Callback callback = d as Callback; if (callback != null) { callback(); } else { throw CreateBroadcastSignatureException(eventType); } } } //Single parameter static public void Broadcast
                                
                                 (string eventType, T arg1) {#if LOG_ALL_MESSAGES || LOG_BROADCAST_MESSAGE Debug.Log("MESSENGER\t" + System.DateTime.Now.ToString("hh:mm:ss.fff") + "\t\t\tInvoking \t\"" + eventType + "\"");#endif OnBroadcasting(eventType); Delegate d; if (eventTable.TryGetValue(eventType, out d)) { Callback
                                 
                                   callback = d as Callback
                                  
                                   ; if (callback != null) { callback(arg1); } else { throw CreateBroadcastSignatureException(eventType); } } } //Two parameters static public void Broadcast
                                   
                                    (string eventType, T arg1, U arg2) {#if LOG_ALL_MESSAGES || LOG_BROADCAST_MESSAGE Debug.Log("MESSENGER\t" + System.DateTime.Now.ToString("hh:mm:ss.fff") + "\t\t\tInvoking \t\"" + eventType + "\"");#endif OnBroadcasting(eventType); Delegate d; if (eventTable.TryGetValue(eventType, out d)) { Callback
                                    
                                      callback = d as Callback
                                     
                                      ; if (callback != null) { callback(arg1, arg2); } else { throw CreateBroadcastSignatureException(eventType); } } } //Three parameters static public void Broadcast
                                      
                                       (string eventType, T arg1, U arg2, V arg3) {#if LOG_ALL_MESSAGES || LOG_BROADCAST_MESSAGE Debug.Log("MESSENGER\t" + System.DateTime.Now.ToString("hh:mm:ss.fff") + "\t\t\tInvoking \t\"" + eventType + "\"");#endif OnBroadcasting(eventType); Delegate d; if (eventTable.TryGetValue(eventType, out d)) { Callback
                                       
                                         callback = d as Callback
                                        
                                         ; if (callback != null) { callback(arg1, arg2, arg3); } else { throw CreateBroadcastSignatureException(eventType); } } } #endregion} //This manager will ensure that the messenger's eventTable will be cleaned up upon loading of a new level.public sealed class MessengerHelper : MonoBehaviour { void Awake () { DontDestroyOnLoad(gameObject); } //Clean up eventTable every time a new level loads. public void OnDisable() { Messenger.Cleanup(); }}
                                        
                                       
                                      
                                     
                                    
                                   
                                  
                                 
                                
                               
                              
                             
                            
                           
                          
                         
                        
                       
                      
                     
                    
                   
                  
                 
                
               
              
             
            
           
          
         
        
       
      
     

然后就可以开始使用了，Messager.Broadcast()这样就好比我们发送了一条广播。

void Update()    {        if(Input.GetMouseButtonDown(0))        {            Messenger.Broadcast("Send");        }    }

在需要这条广播的类中来接受它，同样是刚刚说的Script类。接受广播的标志是 Messager.AddListener()参数1表示广播的名称，参数2表示广播所调用的方法。

using UnityEngine;using System.Collections; public class Script : MonoBehaviour {     void Awake()    {        Messenger.AddListener( "Send", DoSomething );    }    public void DoSomething()    {        Debug.Log("DoSomething");    }}

这样一来，只要发送名称为”Send”的方法，就可以在别的类中接收它了。

我们在说说如何通过广播来传递参数,这也是那天那个哥们主要问我的问题。（其实是维基百科上写的不是特别特别的清楚，那哥们误解了）在Callback中可以看出参数最多可以是三个，参数的类型是任意类型，也就是说我们不仅能传递 int float bool 还能传递gameObject类型。

如下所示，发送广播的时候传递了两个参数，参数1是一个游戏对象，参数2是一个int数值。

void Update()    {        if(Input.GetMouseButtonDown(0))        {            GameObject cube = GameObject.Find("Cube");            Messenger.Broadcast
     
      ("Send",cube,1980);        }    }
     

 然后是接受的地方 参数用<>存在一起。游戏对象也可以完美的传递。

using UnityEngine;using System.Collections; public class Script : MonoBehaviour {     void Awake()    {        Messenger.AddListener
     
      ( "Send", DoSomething );    }    public void DoSomething(GameObject obj,int i)    {        Debug.Log("name " + obj.name + " id =" + i);    }}
     

如果传递一个参数<T>

两个参数<T,T>

三个参数<T,T,T>   

怎么样使用起来还是挺简单的吧？

我觉得项目中最好不要大量的使用代理事件这类的方法（根据需求而定），虽然可以让你的代码非常的简洁，但是它的效率不高大概比直接调用慢5-倍左右吧，就好比美好的东西一定都有瑕疵一样。 还记得Unity自身也提供了一种发送消息的方法吗？，用过的都知道效率也非常低下，虽然我们看不到它具体实现的源码是如何实现的，但是我觉得原理可能也是这样的。