How to get the type Nullable <Enum>?

Question

How can you do something like the following in C #?

Type _nullableEnumType = typeof(Enum?); 

I think the best question is why you cannot do it when you can do it:

 Type _nullableDecimalType = typeof(decimal?); 

Answer 1

Enum not an enumeration - it is a base class for enumerations and is a reference type (i.e. a class ). Enum? that mean Enum? is illegal because Nullable<T> has a limit on T : struct , and Enum does not satisfy this.

So: use typeof(Nullable<>).MakeGenericType(enumTypeKnownAtRuntime) or, more simply, typeof(EnumTypeKnownAtCompileTime?)

You may also notice that:

 Enum x = {some value}; 

is a boxing operation , so usually you should avoid using Enum as a parameter, etc.