How to use an array as multiple indexs in javascript?

Question

To explore a json file i use an array to stock the path to the actual location as follow: 1- path are stocked to a html data-indexs="parent,child,etc.." 2- in Javascript i use split to convert the data-indexs string into an array 3- i want to convert this array into a multiple indexs path.

function previewIndex (index)     
{         
   var indexspath = index.split(',');         
   var initialindex = index;         
   var selected = Json_object.obj[indexspath];         
   var preview = '';         
   console.log(indexspath);

It works fin when there is only 1 element in the table // console : Array [ "features" ] But doesn't with multiple elements // console : Array [ "features", "geometry" ]

So how can i convert this second array into a path to access geometry on my object ?

Thanks for your help !