Why don't I get InvalidCastException when casting enum to integer fails?

Question

public enum Animal
{
    Dog = 1,
    Cat = 2,
    Cow = 3
}

int animalID = 4;
if ((Animal)animalID == Animal.Dog) // does not throw exception

animalID can't be casted to Animal.
Why don't I get InvalidCastException when casting enum to integer fails?

Daniel what happens if you actually assign the cast to another object and check the value of the object after the assignment? you are just comparing with == wich does return a value but in fact is not really assigning anything... — Davide Piras
– Davide Piras, Commented Feb 17, 2011 at 9:07
See this as well: stackoverflow.com/questions/618305/enum-casting — PHeiberg
– PHeiberg, Commented Feb 17, 2011 at 9:10

ChrisF · Accepted Answer · 2015-10-07 12:44:03Z

11

Because it's not an invalid cast.

The value you are casting is out of range for the enum (in this case) but it's not invalid.

As the approved types for an enum are byte, sbyte, short, ushort, int, uint, long, or ulong a cast from integer to enum is perfectly legal.

answered Feb 17, 2011 at 9:07

ChrisF

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Comments

Community · Accepted Answer · 2017-05-23 12:09:02Z

1

This is an intended behaviour and can be pretty useful. Consider enums defined with the [Flag] attribute.