Parsing Complex User Inputs

I have been handed the task of updating and maintaining a web
application, written in ASP and Javascript, that takes complex
user inputs in HTML form and submits them to server-side ASP
pages for processing. The problem is, the user inputs can
become very complex, and the way this application was developed,
the inputs are all concatenated into monstrously long strings
of text that are then submited as <hidden> inputs in HTML forms
and parsed by the server-side ASP. This results in hideous strings
that go on and on like
johnsmith~1232^01^Yes^no~~|43|april

etc. etc. This code is an incredible pain to maintain and update.
There has got to be a better way to do this. I am required to
use javascript and vbscript in ASP pages on the client side,
and ASP pages for processing data on the server side. I can't
switch to a different technology, or use .NET, or anything like
that. I have to use JS and VBScript to get intricate and lengthy
user inputs and submit them for processing. I would like to
store these inputs in objects somehow and then get the data
from those objects, if possible.