How do I access the data from the xmlHTTPRequest?

I'm doing some dynamic loading of CSV files, and I am trying to write up a little script to automatically load the first line of the file as the column names.

After table.request(); is performed, how do I access the requested data?

if anyone can show me where the data is, i've already written the javascript:

var data = xmlhttp.responseText.split(/\n/)[0].split(",")


i just need to know how to access xmlhttp.responseText

alright i think i found it...
var request=new XMLHttpRequest()