C#传递参数-动态事件订阅
我的控制器中有以下内容，并希望将float类型的x、y和z传递给订阅者。然而，我在理解上有些困难。我需要调整什么才能将浮动（x，y，z）作为参数传递？多谢各位C#传递参数-动态事件订阅,c#,.net,events,delegates,observer-pattern,C#,.net,Events,Delegates,Observer Pattern,我的控制器中有以下内容，并希望将float类型的x、y和z传递给订阅者。然而，我在理解上有些困难。我需要调整什么才能将浮动（x，y，z）作为参数传递？多谢各位 private void ProcessEvents() { if(Input.GetMouseButtonDown(1)) { // Data to be passed to subscribers float x = Input.mousePosition.x; floa
private void ProcessEvents()
{
if(Input.GetMouseButtonDown(1))
{
// Data to be passed to subscribers
float x = Input.mousePosition.x;
float y = Input.mousePosition.y;
float z = Input.mousePosition.z;
var publisher = new EventPublisher();
var handler = new Handler();
// Void delegate with one parameter
string eventName = "RightClickEvent";
var rightClickEvent = publisher.GetType().GetEvent(eventName);
rightClickEvent.AddEventHandler(publisher, EventProxy.Create<int>(rightClickEvent, i=>Debug.LogError(i + "!")));
publisher.PublishEvents();
}
}
public class EventPublisher
{
public event EventHandler<ExampleEventArgs> RightClickEvent;
/// <summary>
/// Publishes the events.
/// </summary>
public void PublishEvents()
{
if(RightClickEvent != null)
{
RightClickEvent(this, new ExampleEventArgs{IntArg = 5});
}
}
}
static class EventProxy
{
// Void delegate with one parameter
static public Delegate Create<T>(EventInfo evt, Action<T> d)
{
var handlerType = evt.EventHandlerType;
var eventParams = handlerType.GetMethod("Invoke").GetParameters();
//lambda: (object x0, ExampleEventArgs x1) => d(x1.IntArg)
var parameters = eventParams.Select(p=>Expression.Parameter(p.ParameterType,"x")).ToArray();
var arg = getArgExpression(parameters[1], typeof(T));
var body = Expression.Call(Expression.Constant(d),d.GetType().GetMethod("Invoke"), arg);
var lambda = Expression.Lambda(body,parameters);
return Delegate.CreateDelegate(handlerType, lambda.Compile(), "Invoke", false);
}
// Returns an expression that represents an argument to be passed to the delegate
static Expression getArgExpression(ParameterExpression eventArgs, Type handlerArgType)
{
if(eventArgs.Type == typeof(ExampleEventArgs) && handlerArgType == typeof(int))
{
//"x1.IntArg"
var memberInfo = eventArgs.Type.GetMember("IntArg")[0];
return Expression.MakeMemberAccess(eventArgs,memberInfo);
}
throw new NotSupportedException(eventArgs + "->" + handlerArgType);
}
// Void delegates with no parameters
static public Delegate Create(EventInfo evt, Action d)
{
var handlerType = evt.EventHandlerType;
var eventParams = handlerType.GetMethod("Invoke").GetParameters();
//lambda: (object x0, EventArgs x1) => d()
var parameters = eventParams.Select(p=>Expression.Parameter(p.ParameterType,"x"));
var body = Expression.Call(Expression.Constant(d),d.GetType().GetMethod("Invoke"));
var lambda = Expression.Lambda(body,parameters.ToArray());
return Delegate.CreateDelegate(handlerType, lambda.Compile(), "Invoke", false);
}
}
静态类EventProxy
{
//具有一个参数的Void委托
静态公共委托创建（EventInfo evt，操作d）
{
var handlerType=evt.EventHandlerType；
var eventParams=handlerType.GetMethod（“调用”）.GetParameters（）；
//lambda：（对象x0，ExampleEventArgs x1）=>d（x1.IntArg）
var parameters=eventParams.Select（p=>Expression.Parameter（p.ParameterType，“x”））.ToArray（）；
var arg=getArgExpression（参数[1]，类型（T））；
var body=Expression.Call（Expression.Constant（d），d.GetType（）.GetMethod（“Invoke”），arg）；
var lambda=表达式.lambda（主体，参数）；
返回Delegate.CreateDelegate（handlerType，lambda.Compile（），“Invoke”，false）；
}
//返回表示要传递给委托的参数的表达式
静态表达式GetTargetExpression（ParameterExpression eventArgs，类型handlerArgType）
{
if（eventArgs.Type==typeof（例如eventArgs）和&handlerArgType==typeof（int））
{
//“x1.IntArg”
var memberInfo=eventArgs.Type.GetMember（“IntArg”）[0]；
返回表达式.MakeMemberAccess（eventArgs、memberInfo）；
}
抛出新的NotSupportedException（eventArgs+“->”+handlerArgType）；
}
//没有参数的无效委托
静态公共委托创建（EventInfo evt，操作d）
{
var handlerType=evt.EventHandlerType；
var eventParams=handlerType.GetMethod（“调用”）.GetParameters（）；
//lambda：（对象x0，事件参数x1）=>d（）
var parameters=eventParams.Select（p=>Expression.Parameter（p.ParameterType，“x”）；
var body=Expression.Call（Expression.Constant（d），d.GetType（）.GetMethod（“Invoke”）；
var lambda=Expression.lambda（body，parameters.ToArray（））；
返回Delegate.CreateDelegate（handlerType，lambda.Compile（），“Invoke”，false）；
}
}
getArgExpression// Returns a List of expressions that represent the arguments to be passed to the delegate
static IEnumerable<Expression> getArgExpression(ParameterExpression eventArgs, Type handlerArgType)
{
if (eventArgs.Type == typeof(ExampleEventArgs) && handlerArgType == typeof(int))
{
//"x1.IntArg"
var memberInfo = eventArgs.Type.GetMember("IntArg")[0];
return new List<Expression> { Expression.MakeMemberAccess(eventArgs, memberInfo) };
}
if (eventArgs.Type == typeof(MousePositionEventArgs) && handlerArgType == typeof(float))
{
//"x1.X"
var xMemberInfo = eventArgs.Type.GetMember("X")[0];
//"x1.Y"
var yMemberInfo = eventArgs.Type.GetMember("Y")[0];
//"x1.Z"
var zMemberInfo = eventArgs.Type.GetMember("Z")[0];
return new List<Expression>
{
Expression.MakeMemberAccess(eventArgs, xMemberInfo),
Expression.MakeMemberAccess(eventArgs, yMemberInfo),
Expression.MakeMemberAccess(eventArgs, zMemberInfo),
};
}
throw new NotSupportedException(eventArgs + "->" + handlerArgType);
}
// Void delegate with three parameters
static public Delegate Create<T>(EventInfo eventInformation, Action<T, T, T> lambdaDelegate)
{
var handlerType = eventInformation.EventHandlerType;
var eventParams = handlerType.GetMethod("Invoke").GetParameters();
//lambda: (object x0, ExampleEventArgs x1) => d(x1.X,x1.Y,x1.Z)
var parameters = eventParams.Select(p => Expression.Parameter(p.ParameterType, "x")).ToArray();
var arg = getArgExpression(parameters[1], typeof(T));
var body = Expression.Call(Expression.Constant(lambdaDelegate), lambdaDelegate.GetType().GetMethod("Invoke"), arg);
var lambda = Expression.Lambda(body, parameters);
return Delegate.CreateDelegate(handlerType, lambda.Compile(), "Invoke", false);
}
//具有三个参数的Void委托
静态公共委托创建（事件信息、事件信息、操作lambdaDelegate）
{
var handlerType=eventInformation.EventHandlerType；
var eventParams=handlerType.GetMethod（“调用”）.GetParameters（）；
//lambda：（对象x0，ExampleEventArgs x1）=>d（x1.X，x1.Y，x1.Z）
var parameters=eventParams.Select（p=>Expression.Parameter（p.ParameterType，“x”））.ToArray（）；
var arg=getArgExpression（参数[1]，类型（T））；
var body=Expression.Call（Expression.Constant（lambdaDelegate），lambdaDelegate.GetType（）.GetMethod（“Invoke”），arg）；
var lambda=表达式.lambda（主体，参数）；
返回Delegate.CreateDelegate（handlerType，lambda.Compile（），“Invoke”，false）；
}
rightClickEvent.AddEventHandler(publisher, EventProxy.Create<float>(rightClickEvent, (t, u, v) => Console.Write(t + "x" + u + "x" + v + "!")));
rightClickEvent.AddEventHandler（publisher，EventProxy.Create（rightClickEvent，（t，u，v）=>Console.Write（t+“x”+u+“x”+v+”））；
if（Type==typeof）（…）我需要更多的时间来制定解决方案，但如果你真的感兴趣，我可以试着写下来，然后发布。好的，所以我读了你所说的以类似MVC的风格解耦应用程序模块。我通常喜欢使用强类型代码，即使是在使用反射时，但我对MVC比较陌生，不知道e推荐做法。你比我更了解你的要求，所以我只是编辑了Nguyen的解决方案，因为我相信他使用了一些文件中未包含的扩展名，并将结果发布在这里。所有功劳都归他所有
很抱歉回复太晚，但您似乎在别处找到了解决方案：），祝您好运。非常感谢您的回复。我目前正在尽最大努力改进我的活动实施，如果能为我提供更好的解决方案，我将不胜感激。谢谢。在联机搜索时，我看到您的代码片段取自，此实现要求您可以使用eventname注册事件处理程序。如果你能给我一些关于你到底想要实现什么的细节，我可以想出一个更适合你需要的解决方案。您是否只需要提出并处理mouseeventarg，还是需要针对多个通用场景的解决方案？这确实是一个片段。我的目标是创建一个通用的解决方案，该解决方案将为多种情况接受类似类型的参数。例如，MouseEventArgs和WorldPositionArgs都采用X、Y、Z浮动。希望这能对您有所帮助，再次感谢您的帮助。简单地解释一下我正在尝试做的事情：我的目标是使我的应用程序的每个功能保持解耦。特性以类似MVC的模式构建，其控制器充当入口点。功能控制器负责订阅主应用程序事件。我正在给我的主应用程序添加一个突出显示功能
public class MousePositionEventArgs : EventArgs
{
public float X { get; set; }
public float Y { get; set; }
public float Z { get; set; }
}
// Void delegate with three parameters
static public Delegate Create<T>(EventInfo eventInformation, Action<T, T, T> lambdaDelegate)
{
var handlerType = eventInformation.EventHandlerType;
var eventParams = handlerType.GetMethod("Invoke").GetParameters();
//lambda: (object x0, ExampleEventArgs x1) => d(x1.X,x1.Y,x1.Z)
var parameters = eventParams.Select(p => Expression.Parameter(p.ParameterType, "x")).ToArray();
var arg = getArgExpression(parameters[1], typeof(T));
var body = Expression.Call(Expression.Constant(lambdaDelegate), lambdaDelegate.GetType().GetMethod("Invoke"), arg);
var lambda = Expression.Lambda(body, parameters);
return Delegate.CreateDelegate(handlerType, lambda.Compile(), "Invoke", false);
}
rightClickEvent.AddEventHandler(publisher, EventProxy.Create<float>(rightClickEvent, (t, u, v) => Console.Write(t + "x" + u + "x" + v + "!")));
namespace Dynamics
{
public static class DynamicHandler
{
/// <summary>
/// Invokes a static delegate using supplied parameters.
/// </summary>
/// <param name="targetType">The type where the delegate belongs to.</param>
/// <param name="delegateName">The field name of the delegate.</param>
/// <param name="parameters">The parameters used to invoke the delegate.</param>
/// <returns>The return value of the invocation.</returns>
public static object InvokeDelegate(this Type targetType, string delegateName, params object[] parameters)
{
return ((Delegate)targetType.GetField(delegateName).GetValue(null)).DynamicInvoke(parameters);
}
/// <summary>
/// Invokes an instance delegate using supplied parameters.
/// </summary>
/// <param name="target">The object where the delegate belongs to.</param>
/// <param name="delegateName">The field name of the delegate.</param>
/// <param name="parameters">The parameters used to invoke the delegate.</param>
/// <returns>The return value of the invocation.</returns>
public static object InvokeDelegate(this object target, string delegateName, params object[] parameters)
{
return ((Delegate)target.GetType().GetField(delegateName).GetValue(target)).DynamicInvoke(parameters);
}
/// <summary>
/// Adds a dynamic handler for a static delegate.
/// </summary>
/// <param name="targetType">The type where the delegate belongs to.</param>
/// <param name="fieldName">The field name of the delegate.</param>
/// <param name="func">The function which will be invoked whenever the delegate is invoked.</param>
/// <returns>The return value of the invocation.</returns>
public static Type AddHandler(this Type targetType, string fieldName,
Func<object[], object> func)
{
return InternalAddHandler(targetType, fieldName, func, null, false);
}
/// <summary>
/// Adds a dynamic handler for an instance delegate.
/// </summary>
/// <param name="target">The object where the delegate belongs to.</param>
/// <param name="fieldName">The field name of the delegate.</param>
/// <param name="func">The function which will be invoked whenever the delegate is invoked.</param>
/// <returns>The return value of the invocation.</returns>
public static Type AddHandler(this object target, string fieldName,
Func<object[], object> func)
{
return InternalAddHandler(target.GetType(), fieldName, func, target, false);
}
/// <summary>
/// Assigns a dynamic handler for a static delegate or event.
/// </summary>
/// <param name="targetType">The type where the delegate or event belongs to.</param>
/// <param name="fieldName">The field name of the delegate or event.</param>
/// <param name="func">The function which will be invoked whenever the delegate or event is fired.</param>
/// <returns>The return value of the invocation.</returns>
public static Type AssignHandler(this Type targetType, string fieldName,
Func<object[], object> func)
{
return InternalAddHandler(targetType, fieldName, func, null, true);
}
/// <summary>
/// Assigns a dynamic handler for a static delegate or event.
/// </summary>
/// <param name="target">The object where the delegate or event belongs to.</param>
/// <param name="fieldName">The field name of the delegate or event.</param>
/// <param name="func">The function which will be invoked whenever the delegate or event is fired.</param>
/// <returns>The return value of the invocation.</returns>
public static Type AssignHandler(this object target, string fieldName, Func<object[], object> func)
{
return InternalAddHandler(target.GetType(), fieldName, func, target, true);
}
private static Type InternalAddHandler(Type targetType, string fieldName,
Func<object[], object> func, object target, bool assignHandler)
{
Type delegateType;
var bindingFlags = BindingFlags.Public | BindingFlags.NonPublic |
(target == null ? BindingFlags.Static : BindingFlags.Instance);
var eventInfo = targetType.GetEvent(fieldName, bindingFlags);
if (eventInfo != null && assignHandler)
throw new ArgumentException("Event can be assigned. Use AddHandler() overloads instead.");
if (eventInfo != null)
{
delegateType = eventInfo.EventHandlerType;
var dynamicHandler = BuildDynamicHandler(delegateType, func);
eventInfo.GetAddMethod(true).Invoke(target, new Object[] { dynamicHandler });
}
else
{
var fieldInfo = targetType.GetField(fieldName);
//,target == null ? BindingFlags.Static : BindingFlags.Instance);
delegateType = fieldInfo.FieldType;
var dynamicHandler = BuildDynamicHandler(delegateType, func);
var field = assignHandler ? null : target == null
? (Delegate)fieldInfo.GetValue(null)
: (Delegate)fieldInfo.GetValue(target);
field = field == null
? dynamicHandler
: Delegate.Combine(field, dynamicHandler);
if (target != null)
target.GetType().GetField(fieldName).SetValue(target, field);
else
targetType.GetField(fieldName).SetValue(null, field);
//(target ?? targetType).SetFieldValue(fieldName, field);
}
return delegateType;
}
/// <summary>
/// Dynamically generates code for a method whose can be used to handle a delegate of type
/// <paramref name="delegateType"/>. The generated method will forward the call to the
/// supplied <paramref name="func"/>.
/// </summary>
/// <param name="delegateType">The delegate type whose dynamic handler is to be built.</param>
/// <param name="func">The function which will be forwarded the call whenever the generated
/// handler is invoked.</param>
/// <returns></returns>
public static Delegate BuildDynamicHandler(this Type delegateType, Func<object[], object> func)
{
var invokeMethod = delegateType.GetMethod("Invoke");
var parameters = invokeMethod.GetParameters().Select(parm =>
Expression.Parameter(parm.ParameterType, parm.Name)).ToArray();
var instance = func.Target == null ? null : Expression.Constant(func.Target);
var convertedParameters = parameters.Select(parm => Expression.Convert(parm, typeof(object))).Cast<Expression>().ToArray();
var call = Expression.Call(instance, func.Method, Expression.NewArrayInit(typeof(object), convertedParameters));
var body = invokeMethod.ReturnType == typeof(void)
? (Expression)call
: Expression.Convert(call, invokeMethod.ReturnType);
var expr = Expression.Lambda(delegateType, body, parameters);
return expr.Compile();
}
}
}
class TestClass
{
private void Test()
{
TestInstance();
TestStatic();
}
private void TestInstance()
{
var eventClass = new EventClass();
eventClass.InvokeDelegate("InstanceEventRaiseDelegate");
eventClass.AddHandler("InstanceEvent", parameters =>
{
return true;
});
eventClass.AddHandler("InstanceEventRaiseDelegate", parameters =>
{
return true;
});
eventClass.InvokeDelegate("InstanceEventRaiseDelegate");
eventClass.AssignHandler("InstanceEventRaiseDelegate", parameters =>
{
return true;
});
eventClass.InvokeDelegate("InstanceEventRaiseDelegate");
}
private void TestStatic()
{
typeof(EventClass).InvokeDelegate("StaticEventRaiseDelegate");
typeof(EventClass).AddHandler("StaticEvent", parameters =>
{
return true;
});
typeof(EventClass).AddHandler("StaticEventRaiseDelegate", parameters =>
{
return true;
});
typeof(EventClass).InvokeDelegate("StaticEventRaiseDelegate");
typeof(EventClass).AssignHandler("StaticEventRaiseDelegate", parameters =>
{
return true;
});
typeof(EventClass).InvokeDelegate("StaticEventRaiseDelegate");
}
public class EventClass
{
#region Instance
public EventClass()
{
InstanceEventRaiseDelegate = OnInstanceEvent;
}
public Action InstanceEventRaiseDelegate;
public event EventHandler InstanceEvent;
public void OnInstanceEvent()
{
if (InstanceEvent != null)
InstanceEvent(this, EventArgs.Empty);
}
#endregion
#region Static
static EventClass()
{
StaticEventRaiseDelegate = OnStaticEvent;
}
public static Action StaticEventRaiseDelegate;
public static event EventHandler StaticEvent;
public static void OnStaticEvent()
{
if (StaticEvent != null)
StaticEvent(null, EventArgs.Empty);
}
#endregion
}
}