C# - Extracting Data From An ASPX Page?

The task is: given a web application that returns a table with pagination, do a software that "reads and parses it" since there is nothing like a webservice that provides the raw data. It's like a "spider" or a "crawler" application to steal data that is not meant to be accessed programmatically.

Now the thing: the application is made with standart aspx webform engine, so nothing like standard URLs or posts, but the dreadful postback engine crowded with javascript and non accessible html. The pagination links call the infamous javascript:__doPostBack(param, param) so I think it wouldn't even work if I try even to simulate clicks on those links.

There are also inputs to filter the results and they are also part of the postback mechanism, so I can't simulate a regular post to get the results.

I was forced to do something like this in the past, but it was on a standard-like website with parameters in the querystring like pagesize and pagenumber so I was able to sort it out.

Anyone has a vague idea if this is doable, or if I should tell to my boss to quit asking me to do this retarded stuff?

EDIT: maybe I was a bit unclear about what I have to achieve. I have to parse, extract and convert that data in another format - let's say excel - and not just read it. And this stuff must be automated without user input. I don't think Selenium would cut it.

EDIT: I just blogged about this situation. If anyone is interested can check my post at [URL] and comment about that.