Dynamic redirect with &gotoid

Problem: eForm are treating the page id it should redirect too as a string, and not a integer, and are causing a error:

Scenario:

On some pages I have forms made with Ditto. When the form are submitted to Eform I populate the information with a snippet function combined with &eFormOnBeforeFormMerge. Without any problems!

The tree are something like this:

Categori 1
- Subject 1
-- Subpage, posting to eForm page with the page ID of categori 1
- Subject 2
-- Time, posting to eForm page with the page ID of categori 1

Categori 2
- Subject 1
-- Subpage, posting to eForm page with the page ID of categori 2
- Subject 2
-- Subpage, posting to eForm page with the page ID of categori 2

Etc.

Eform page
- Receipt for Categori 1
- Receipt for Categori 2

Etc.

All the Subpages are posting the information to a page with eForm, and are including the ultimate page ID (Categori). With the snippet function, I then with simple if elseif statements declare which page (ID) Eform are redirecting to, after submitting, using &gotoid=`[+redirectToID+]`

So far, so good, but eForm are treating my [+redirectToID+] as a string, where it should be numeric. I have tried different solutions to convert it to int, but without any luck.

Are there any out there with a good solution, and maybe with some code examples too something similar?