Generics and delegates

[MP]

Hi,
I am using VS 2005 and I am trying to write a Generic class to fire
asynchronously the remoting events from a server.
I declare the generic like so...
public class AsyncEvent<Del> where Del : Delegate
and I get this error... 'Constraint cannot be special class
'System.Delegate"...

I understand what the message says, but does this mean that I absolutly
cannot write a generic for delegates... Is there another type I can use?

-Martin

 

[Mickey Williams [C# MVP]]

Hi,
I am using VS 2005 and I am trying to write a Generic class to fire
asynchronously the remoting events from a server.
I declare the generic like so...
public class AsyncEvent<Del> where Del : Delegate
and I get this error... 'Constraint cannot be special class
'System.Delegate"...

I understand what the message says, but does this mean that I absolutly
cannot write a generic for delegates... Is there another type I can use?

-Martin

Delegates can be parameterized. I think you're writing the dependency upside
down:

public delegate void RemotingCallback<T>(object sender, T e) where T:
EventArgs;
public event RemotingCallback<MyEventArgs> ServerNotify;

 

[MP]

Thank you!

You were right, I was upside-down.

-MP

 

[Andreas Huber]

Mickey Williams [C# MVP] wrote:
[snip]

Delegates can be parameterized. I think you're writing the dependency upside
down:

public delegate void RemotingCallback<T>(object sender, T e) where T:

EventArgs;
public event RemotingCallback<MyEventArgs> ServerNotify;

So you think it is *always* bad design to require a Delegate for a
generic parameter? If so, why?

Regards,