PHP CSV columns into arrays

Placebo

Basically, i want to make a system where a user can upload a CSV file and pick what columns they want to upload/process

I can do this fine by using fopen and foreach, but since the number of the column may vary from CSV to CSV....

i can store the picked columns in an array, eg picked[]= "1,2,4"; //from 1,2,3,4 columns
comma seperated or anyway i want.

but how can i use something like list(1,2,4) = explode("," , theData[]);

where i can load 1,2,4, in there dynamically, or even 1,2,3,4 and then i can ignore 3.