ExistsIn validation fails with non-int backed Enums

[fsateler]

The currently released version (2.1.0), currently casts enums to int when fetching possible values, to be able to compare the string representation.

This fails with short or long backed enums with an InvalidCastException.

This could be fixed by using Convert.ToInt32 instead. But I wonder if this is the right approach at all? I would have expected that the ExistsIn attribute refers to a property that has the same type as the target property. If I'm interpreting the code correctly, the following code would fail:

[ExistsIn("Values", "Key", "Value")]
public MyEnum Property {get;set;}
public Dictionary<MyEnum,string> Values = ...;

Because only the values fetched from Values are converted to int, but the Property value is not.

[robdmoore]

Weird. Off the top of my head I'm not sure why we are converting to an int. It makes more sense to me to always deal with the string value of the enum not the int.

There must be a reason why we have the cast though.

If you can work out why it's done that way and a solution that keeps as string or fixes your problem in another way I'm happy to take a PR.

Out of curiosity though, why would you use an enum backed by something that isn't an int? I must admit, I've never come across that before in any codebases I've seen :P

[fsateler]

A possible solution would be to use Convert.ToInt32. It should be a bit slower, but this part is not performance critical anyway.

Out of curiosity though, why would you use an enum backed by something that isn't an int? I must admit, I've never come across that before in any codebases I've seen :P

It is backed by a short, because that is how it is stored in the database...

[robdmoore]

Fair enough.

I'm comfortable accepting a PR that does a Convert.ToInt32, but I'm still curious why it even casts them to an int in the first place (I realise I'm probably the one that wrote it, but I can't remember specifics since it was years ago now haha).

[Devika-Rudagi]

Hi, is this issue still open? I would like to work on it