Generic C# method taking where the enum value as a parameter

Question

Possible Duplicate:
Create Generic method constraining T to an Enum

Given a generic method that only operates on enum values

static void <T> method(T enum) where T ?????
{
     // do something with enum...
}

How do I constrain T such that only enum values are accepted? I've tried using struct however this disallows the use calling my method with a nullable enum type.

score 4 · Accepted Answer · answered Sep 08 '11 at 11:05

4

Generic constraints on enum types are impossible in C#, but are possible in IL. Have a look at Jon Skeet's project, Unconstrained Melody, it will allow you to constraint your generic methods to enums.

answered Sep 08 '11 at 11:05

Igal Tabachnik

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Thats an example of how to do this using IL rather than a library to let you do this yourself, but very interesting all the same! – Justin Sep 08 '11 at 11:11

score 2 · Answer 2 · answered Sep 08 '11 at 11:05

2

In C# you can't. For some reason I don't know the C# specification explicitly forbids System.Enum as a constraint.

And even then it wouldn't accept nullable enums because nullable enums are no enums.

answered Sep 08 '11 at 11:05

CodesInChaos

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Generic C# method taking where the enum value as a parameter

2 Answers2