Question

I have a class X and this class have a event: EventX.

And I have a class B, I register event EventX of objectX to a eventhandler HandlerB of class B.

X objectX = X.GetStaticObject();
objectX.EventX += HandlerB;

How to check EventX of objectX contained eventhandler HandlerB. Thanks.

Notes: objectX is a static global which event can be registered from anywhere with any objects which are not object B.

Answer 1

To check that specifically your HandlerB was registered, you can use Delegate.GetInvocationList() method to get appropriate info.

EDIT:

After V4Vendetta comment I tried to compile code and it failed. I slightly changed it.

To be able to do that check, method Test should be added to X (I assume that it’s static, otherwise use this instead of X):

public static void Test(Delegate delegateToTest)
{
   if (X.EventX != null)
   {
       foreach (Delegate existingHandler in X.EventX.GetInvocationList())
       {
           if (existingHandler == delegateToTest)
           {
               // registered
           }
       }
    }
}

And then test from somewhere where HandlerB is accessible:

X.Test(new EventHandler(HandlerB));