I'm trying to define a dictionary whose value is an Generic Action<>
delegate
private Dictionary<stri ng, List<Action<T>> >
Any ideas on to how specify T or a different collection type more suitable
to this?
Thanks 9  6428 
What is the use-case here? What do you want to do with it? For example,
a plain Action might suffice, using the delegate's target for the
instance (perhaps via a closure)?
Marc
On Tue, 01 Jul 2008 09:56:49 -0700, eric <7ak@!_df.comwr ote:
I'm trying to define a dictionary whose value is an Generic Action<>
delegate
Then rather than what you posted:
private Dictionary<stri ng, List<Action<T>> >
You would use:
Dictionary<stri ng, Action<T>>
Where "T" is of course an actual type, assuming you want to declare a
concrete version of the generic Dictionary.
Any ideas on to how specify T or a different collection type more
suitable
to this?
Meaning what? You "specify T" by putting a valid concrete type in for the
generic type parameter. If that doesn't answer your question, I think you
need to rephrase the question so that you're more clear about what you're
actually trying to accomplish.
Pete
Sorry,
I'm trying to postpone the concrete type definition until runtime and I
do want a List<Action<T>o f generic delegates for every key in the
dictionary.
"Peter Duniho" <Np*********@nn owslpianmk.comw rote in message
news:op******** *******@petes-computer.local. ..
On Tue, 01 Jul 2008 09:56:49 -0700, eric <7ak@!_df.comwr ote:
>I'm trying to define a dictionary whose value is an Generic Action<>
delegate
Then rather than what you posted:
>private Dictionary<stri ng, List<Action<T>> >
You would use:
Dictionary<stri ng, Action<T>>
Where "T" is of course an actual type, assuming you want to declare a
concrete version of the generic Dictionary.
>Any ideas on to how specify T or a different collection type more
suitable
to this?
Meaning what? You "specify T" by putting a valid concrete type in for the
generic type parameter. If that doesn't answer your question, I think you
need to rephrase the question so that you're more clear about what you're
actually trying to accomplish.
Pete
Note that Action<T>, as a multicast delegate, can already support
multiple delegates per instance. Re the generics - what is the
difficulty? If the T is only known at runtime, then you'll need to use
reflection and MakeGenericType () or MakeGenericMeth od() - but if there
*is* no appropriate T you might have to use "object" or something
comparable.
Marc
eric <7ak@!_df.comwr ote:
I'm trying to postpone the concrete type definition until runtime and I
do want a List<Action<T>o f generic delegates for every key in the
dictionary.
As Marc said, you can probably just use a multi-cast delegate to avoid
needing a List.
However, the point about generics is to give you *compile-time* safety.
If you won't know the type at compile time, other than that it's a
delegate, you should probably just make it a
Dictionary<stri ng,Delegate>
--
Jon Skeet - <sk***@pobox.co m>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon_skeet
C# in Depth: http://csharpindepth.com
I swapped out the Dictionary for Hashtable and that was able to give me what
I was after.
Thanks to all for the help.
"Jon Skeet [C# MVP]" <sk***@pobox.co mwrote in message
news:MP******** *************@m snews.microsoft .com...
eric <7ak@!_df.comwr ote:
> I'm trying to postpone the concrete type definition until runtime and
I
do want a List<Action<T>o f generic delegates for every key in the
dictionary.
As Marc said, you can probably just use a multi-cast delegate to avoid
needing a List.
However, the point about generics is to give you *compile-time* safety.
If you won't know the type at compile time, other than that it's a
delegate, you should probably just make it a
Dictionary<stri ng,Delegate>
--
Jon Skeet - <sk***@pobox.co m>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon_skeet
C# in Depth: http://csharpindepth.com
I couldn't make Delegate work with Action<T>. I was really trying to
implement something where
I didn't need to know about a specific delegate type. The end result is
really not as nongeneric in the untype-safe sense as you might think.
"Jon Skeet [C# MVP]" <sk***@pobox.co mwrote in message
news:MP******** *************@m snews.microsoft .com...
eric <7ak@!_df.comwr ote:
>I swapped out the Dictionary for Hashtable and that was able to give me
what
I was after.
Well that's just going completely nongeneric.
Why not use Dictionary<stri ng,Delegate- that at least gives you
*some* safety...
--
Jon Skeet - <sk***@pobox.co m>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon_skeet
C# in Depth: http://csharpindepth.com
eric <7ak@!_df.comwr ote:
I couldn't make Delegate work with Action<T>. I was really trying to
implement something where
I didn't need to know about a specific delegate type.
Which is why you'd need Delegate instead of Action<T>. Then just invoke
it dynamically, which I suspect is what you're having to do anyway.
The end result is really not as nongeneric in the untype-safe sense
as you might think.
You're using Hashtable, which is completely nongeneric and untypesafe.
--
Jon Skeet - <sk***@pobox.co m>
Web site: http://www.pobox.com/~skeet
Blog: http://www.msmvps.com/jon_skeet
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