If dDelegate is a known type (ie Action) you could always cast to it and call it directly.
With that said if you are on .NET3.5 you can use Expression trees to get a fair bit of optimization. My example uses the concurrent dictionary in .NET4 but that's replacable with a normal dictionary and a lock.
The idea is as following: The delegate holds which method it's calling to. For each unique method that is called I create (using Expression trees) a compiled delegate that calls that specific method. Creating a compiled delegate is expensive that's why it's important to cache it but once created the compiled delegate is as fast as a normal delegate.
On my machine 3,000,000 calls took 1 sec with the compiled delegate and 16 sec with DynamicInvoke.
// Comment this line to use DynamicInvoke instead as a comparison
#define USE_FAST_INVOKE
namespace DynInvoke
{
using System;
using System.Collections.Concurrent;
using System.Linq.Expressions;
using System.Reflection;
static class Program
{
delegate void CachedMethodDelegate (object instance, object sender, EventArgs param);
readonly static ConcurrentDictionary<MethodInfo, CachedMethodDelegate> s_cachedMethods =
new ConcurrentDictionary<MethodInfo, CachedMethodDelegate> ();
public static void InvokeExternal(Delegate d, object sender, EventArgs param)
{
if (d != null)
{
//Check each invocation target
foreach (var dDelgate in d.GetInvocationList())
{
if (
dDelgate.Target != null
&& dDelgate.Target is System.ComponentModel.ISynchronizeInvoke
&& ((System.ComponentModel.ISynchronizeInvoke)(dDelgate.Target)).InvokeRequired
)
{
//If target is ISynchronizeInvoke and Invoke is required, invoke via ISynchronizeInvoke
((System.ComponentModel.ISynchronizeInvoke)(dDelgate.Target)).Invoke(dDelgate, new object[] { sender, param });
}
else
{
#if USE_FAST_INVOKE
var methodInfo = dDelgate.Method;
var del = s_cachedMethods.GetOrAdd (methodInfo, CreateDelegate);
del (dDelgate.Target, sender, param);
#else
dDelgate.DynamicInvoke (sender, param);
#endif
}
}
}
}
static CachedMethodDelegate CreateDelegate (MethodInfo methodInfo)
{
var instance = Expression.Parameter (typeof (object), "instance");
var sender = Expression.Parameter (typeof (object), "sender");
var parameter = Expression.Parameter (typeof (EventArgs), "parameter");
var lambda = Expression.Lambda<CachedMethodDelegate>(
Expression.Call (
Expression.Convert (instance, methodInfo.DeclaringType),
methodInfo,
sender,
parameter
),
instance,
sender,
parameter
);
return lambda.Compile ();
}
class MyEventListener
{
public int Count;
public void Receive (object sender, EventArgs param)
{
++Count;
}
}
class MyEventSource
{
public event Action<object, EventArgs> AnEvent;
public void InvokeAnEvent (EventArgs arg2)
{
InvokeExternal (AnEvent, this, arg2);
}
}
static void Main(string[] args)
{
var eventListener = new MyEventListener ();
var eventSource = new MyEventSource ();
eventSource.AnEvent += eventListener.Receive;
var eventArgs = new EventArgs ();
eventSource.InvokeAnEvent (eventArgs);
const int Count = 3000000;
var then = DateTime.Now;
for (var iter = 0; iter < Count; ++iter)
{
eventSource.InvokeAnEvent (eventArgs);
}
var diff = DateTime.Now - then;
Console.WriteLine (
"{0} calls took {1:0.00} seconds (listener received {2} calls)",
Count,
diff.TotalSeconds,
eventListener.Count
);
Console.ReadKey ();
}
}
}
Edit: As OP uses .NET2 I added an example that should be compatible with .NET2 runtime (as I use VS2010 I might use some new language features by mistake but I did compile using .NET2 runtime).
// Comment this line to use DynamicInvoke instead as a comparison
#define USE_FASTER_INVOKE
namespace DynInvoke
{
using System;
using System.Globalization;
using System.Reflection.Emit;
using System.Collections.Generic;
using System.ComponentModel;
using System.Reflection;
static class FasterInvoke
{
delegate void CachedMethodDelegate (object instance, object sender, EventArgs param);
readonly static Dictionary<MethodInfo, CachedMethodDelegate> s_cachedMethods =
new Dictionary<MethodInfo, CachedMethodDelegate> ();
public static void InvokeExternal (Delegate d, object sender, EventArgs param)
{
if (d != null)
{
Delegate[] invocationList = d.GetInvocationList ();
foreach (Delegate subDelegate in invocationList)
{
object target = subDelegate.Target;
if (
target != null
&& target is ISynchronizeInvoke
&& ((ISynchronizeInvoke)target).InvokeRequired
)
{
((ISynchronizeInvoke)target).Invoke (subDelegate, new[] { sender, param });
}
else
{
#if USE_FASTER_INVOKE
MethodInfo methodInfo = subDelegate.Method;
CachedMethodDelegate cachedMethodDelegate;
bool result;
lock (s_cachedMethods)
{
result = s_cachedMethods.TryGetValue (methodInfo, out cachedMethodDelegate);
}
if (!result)
{
cachedMethodDelegate = CreateDelegate (methodInfo);
lock (s_cachedMethods)
{
s_cachedMethods[methodInfo] = cachedMethodDelegate;
}
}
cachedMethodDelegate (target, sender, param);
#else
subDelegate.DynamicInvoke (sender, param);
#endif
}
}
}
}
static CachedMethodDelegate CreateDelegate (MethodInfo methodInfo)
{
if (!methodInfo.DeclaringType.IsClass)
{
throw CreateArgumentExceptionForMethodInfo (
methodInfo,
"Declaring type must be class for method: {0}.{1}"
);
}
if (methodInfo.ReturnType != typeof (void))
{
throw CreateArgumentExceptionForMethodInfo (
methodInfo,
"Method must return void: {0}.{1}"
);
}
ParameterInfo[] parameters = methodInfo.GetParameters ();
if (parameters.Length != 2)
{
throw CreateArgumentExceptionForMethodInfo (
methodInfo,
"Method must have exactly two parameters: {0}.{1}"
);
}
if (parameters[0].ParameterType != typeof (object))
{
throw CreateArgumentExceptionForMethodInfo (
methodInfo,
"Method first parameter must be of type object: {0}.{1}"
);
}
Type secondParameterType = parameters[1].ParameterType;
if (!typeof (EventArgs).IsAssignableFrom (secondParameterType))
{
throw CreateArgumentExceptionForMethodInfo (
methodInfo,
"Method second parameter must assignable to a variable of type EventArgs: {0}.{1}"
);
}
// Below is equivalent to a method like this (if this was expressible in C#):
// void Invoke (object instance, object sender, EventArgs args)
// {
// ((<%=methodInfo.DeclaringType%>)instance).<%=methodInfo.Name%> (
// sender,
// (<%=secondParameterType%>)args
// );
// }
DynamicMethod dynamicMethod = new DynamicMethod (
String.Format (
CultureInfo.InvariantCulture,
"Run_{0}_{1}",
methodInfo.DeclaringType.Name,
methodInfo.Name
),
null,
new[]
{
typeof (object),
typeof (object),
typeof (EventArgs)
},
true
);
ILGenerator ilGenerator = dynamicMethod.GetILGenerator ();
ilGenerator.Emit (OpCodes.Ldarg_0);
ilGenerator.Emit (OpCodes.Castclass, methodInfo.DeclaringType);
ilGenerator.Emit (OpCodes.Ldarg_1);
ilGenerator.Emit (OpCodes.Ldarg_2);
ilGenerator.Emit (OpCodes.Isinst, secondParameterType);
if (methodInfo.IsVirtual)
{
ilGenerator.EmitCall (OpCodes.Callvirt, methodInfo, null);
}
else
{
ilGenerator.EmitCall (OpCodes.Call, methodInfo, null);
}
ilGenerator.Emit (OpCodes.Ret);
return (CachedMethodDelegate)dynamicMethod.CreateDelegate (typeof (CachedMethodDelegate));
}
static Exception CreateArgumentExceptionForMethodInfo (
MethodInfo methodInfo,
string message
)
{
return new ArgumentException (
String.Format (
CultureInfo.InvariantCulture,
message,
methodInfo.DeclaringType.FullName,
methodInfo.Name
),
"methodInfo"
);
}
}
static class Program
{
class MyEventArgs : EventArgs
{
}
class MyEventListener
{
public int Count;
public void Receive (object sender, MyEventArgs param)
{
++Count;
}
}
delegate void MyEventHandler (object sender, MyEventArgs args);
class MyEventSource
{
public event MyEventHandler AnEvent;
public void InvokeAnEvent (MyEventArgs arg2)
{
FasterInvoke.InvokeExternal (AnEvent, this, arg2);
}
}
static void Main (string[] args)
{
MyEventListener eventListener = new MyEventListener ();
MyEventSource eventSource = new MyEventSource ();
eventSource.AnEvent += eventListener.Receive;
MyEventArgs eventArgs = new MyEventArgs ();
eventSource.InvokeAnEvent (eventArgs);
const int count = 5000000;
DateTime then = DateTime.Now;
for (int iter = 0; iter < count; ++iter)
{
eventSource.InvokeAnEvent (eventArgs);
}
TimeSpan diff = DateTime.Now - then;
Console.WriteLine (
"{0} calls took {1:0.00} seconds (listener received {2} calls)",
count,
diff.TotalSeconds,
eventListener.Count
);
Console.ReadKey ();
}
}
}
