InvokeMember is very slow, anyway to avoid this?

Question

I have to do reflection and late binding so i don't know if there is a way to speed things up. Thought I would give it a shot.

This snippet takes about 15 seconds to complete which is way too slow, but seeing how I need to read the metadata.

private static object InvokeCall(Type HostObjectType, Object HostObject, CallType callType, string PropertyOrMethodName, object[] args)
{
    if (callType == CallType.Method)
    {
        return MyObjectType.InvokeMember(PropertyOrMethodName,System.Reflection.BindingFlags.InvokeMethod, null, myObject, args);
    }
}

Answer 1

I assume that 15s is when used in a loop; reflection isn't that slow.

You can speed up reflection (and invoke in particular) by obtaining the MethodInfo and using Delegate.CreateDelegate once. You then cache and re-use the resulting typed delegate (matching the expected call signature). Then use the typed delegate Invoke.

Note untyped delegate invoke is slow; it must be typed. Also; you can be sneaky and use a delegate with an extra (leading) parameter to invoke an instance method against a range of different objects, if you need the target object to change per-call.

For more complex scenarios, Expression or DynamicMethod are useful.

Answer 2

Take a look to Fasterflect - A Fast and Simple Reflection API and Fast Invoker they are ready to use solutions and interesting to study.

If you want to go by your own way check articles: Dodge Common Performance Pitfalls to Craft Speedy Applications and Dynamically Compiled Lambdas vs. Pure Reflection

Answer 3

Try using an expression tree compiled lambda and cache the lambda. I've leveraged this extensively with great success.

http://kohari.org/2009/03/06/fast-late-bound-invocation-with-expression-trees/