Why does enum declaration accept short but not Int16

I want to declare a new enum with non-default underlying type. This works:

public enum MyEnum : short
{ A, B, C, }

But I don't under开发者_StackOverflow中文版stand the reason why this doesn't compile:

public enum MyEnum : System.Int16
{ A, B, C, }

Compiler says

Type byte, sbyte, short, ushort, int, uint, long, or ulong expected

I understand that short is an alias for Int16 on all .NET versions (32/64 bit flavors included). I don't see why the compiler gives a different meaning to the alias in that particular case.

Any explanation?

The syntax is correct. C# specification explicitly states that the enum's underlying type must be byte, sbyte, short, ushort, int, uint, long or ulong.

Read what Microsoft says about this here.

"...The second example is trying to inherit from a type that derives from System.ValueType, which is strictly prohibited..."

Read here: