How can I remove duplicates from a restservice?

[Bernie]

I do have a restservice that contain multiple entries, each with a couple of fields.
One of the fileds is called "Category". Some of the entries are in the same category.
So how can I manage to fill a list with all categories without having duplicates?

Here is the JSON file that feeds the restservice:

http://www.geocockpit2.net/york-trial...

[maxkatz]

No simple way to do it during mapping. You could get the entire response (JSON) and then remove the items that you don't need.