How to add a title when you don't know what you're asking for?

Question

I really don't know how to ask for what I'm asking for ... I'd google if I knew what I was looking for!

So, I have a set of carrierwave versions of images names image00, image01, image02 etc up to image25 stored as:

@photo.main.image00, @photo.main.image01 etc ...

I want to be able to use a controller to post these images out. But I have no idea how to string the request together. I've got objective-c, javascript, Ruby and a host of other languages fighting for space in my head, and Ruby seems to have lost out!

I wish to be able to make a call such as:

@photopiece = Base64.strict_encode64(File.read(@photos.main.imageXX.current_path))

but have no idea how to replace the XX with a digit and still have the file encoded.

I tried:

imagestring = "@photos.main.image#{sendPiece}.current_path"

and then

@photopiece = Base64.strict_encode(File.read(imagestring))

But that did nothing ... I could almost hear the compiler laughing at me (such is my paranoia now!)

So, how do I get the photo names to appear in the form:

@photos.main.imageXX.current_path

such that they can get parsed by strict_encode?

Thanks in advance for help! And reading my ramblings ...

PS. Apologies for the really bad heading! Please change it if you know what I'm asking for!

Answer 1

Maybe, it would be more secure than silly eval(params..):

 number_is_safe = !!Float(sendPiece) rescue false
 if number_is_safe
   path = eval "@photos.main.image#{sendPiece}.current_path"
   @photopiece = Base64.strict_encode(File.read(path))
 end

---

jvnill propose much better solution:

piece = @photos.main.public_send("image#{sendPiece}")
@photopiece = Base64.strict_encode64(File.read(piece.current_path))

Answer 2

You can use public_send

piece = @photos.main.public_send("image#{sendPiece}")
@photopiece = Base64.strict_encode64(File.read(piece.current_path))