Func<EventHandler, get property value from args?

Question

Have tried to solve this for quite a while now, but without luck... My idea was to have some sort of a configuration for different settings, for instance.. controlling how exceptions are handled.

Some of my code :)

public class ErrorEventArgs : EventArgs
{
   public bool Handled { get; set; }
...
...
}

A property in my main class like :

EventHandler<ErrorEventArgs> ErrorConfiguration {get; set;}

I then have an OnError where I need to know value of Handled,

internal void OnError(ErrorEventArgs args)
{
   Func<EventHandler<ErrorEventArgs>, bool> IsHandled;

   IsHandled = ev => ??? // invoke ErrorConfiguration?

   if (ErrorConfiguration != null && IsHandled(ErrorConfiguration ))
                error(this, args);
}

How can this be solved?

I can do like this, if it's the EventHandler without the Func, but I want to encapsulate the boolean expression. Why cant I chain the lambda... :(

EventHandler<ErrorEventArgs> IsHandled;
IsHandled = (sender, e) => e.ErrorContext.Handled;

Answer 1

I am not completely sure what you want to achieve, exactly. But you can do something like:

IsHandled = ev => { ev(this, args); return args.Handled; };

Even though I am not sure this is more readable, faster, cleaner, or anything like that. I would just go with something like

if (ErrorConfiguration != null) ErrorConfiguration(this, args);
if (!args.Handled) error(this, args);

Answer 2

You really don't need any lambda to call your just need to call your delegate directly:

internal void OnError(ErrorEventArgs args)
{
   if (ErrorConfiguration != null)
       ErrorConfiguration(this, args);

   if (args.Handled)
       error(this, args);
}

If you want to the use the same thing in a lambda, you'll have do to this, which will take more lines of code:

internal void OnError(ErrorEventArgs args) {   
Func<EventHandler<ErrorEventArgs>, bool> IsHandled;

   IsHandled = ev => {
        ErrorConfiguration(this, ev);
        return ev.Handled;   
   };

   if (ErrorConfiguration != null && IsHandled(ErrorConfiguration ))
       error(this, args); 
}