Will there be generic attributes in C# 4?

Question

So - if there isn't particular reason why there isn't generic attributes,
I'm wondering - maybe they will be implemented?

Those would be great for ASP.NET MVC action filters.

Luckily there are alternative ways to attach filters nowadays... — Arnis Lapsa, Mar 14 '11 at 21:19

score 20 · Accepted Answer · answered Jul 31 '09 at 07:37

20

I haven't seen any evidence of this in the 4.0 spec... so I believe the answer is "no".

answered Jul 31 '09 at 07:37

Marc Gravell

4

It's hard to accept answer which i didn't want to hear. -_- – Arnis Lapsa Jul 31 '09 at 07:59
11

Correct. That feature continues to be very low on the priority list. – Eric Lippert Jul 31 '09 at 15:35
6

Always good to get a definitive answer; thanks Eric. – Marc Gravell Jul 31 '09 at 20:38

score 8 · Answer 2 · answered Jul 31 '09 at 07:38

8

C# 4 specification does not mention generics in attributes.

answered Jul 31 '09 at 07:38

Lloyd

score 1 · Answer 3 · answered Jan 11 '11 at 11:32

1

Shame, stumbled across a case where I wanted to use this in a ValidationAttribute.

Something that can check whether a given collection is empty. In general, this could be with a generic or non generic parameter.

public override Boolean IsValid(Object value)
    {
        var v = value as ICollection<T>;

        return v.Count > 0;
    }

Would be useful if I could do this.

answered Jan 11 '11 at 11:32

Jamie

I'd also like to combine generics and the ValidationAttribute. It would be nice if the ValidationAttribute implemented an IValidatable and inherited from Attribute. – Mar 14 '11 at 20:38

3 Answers3