I am using Ajax functionality to retrieve my content and I need to export PDF on success of jQuery.ajax(). How can I do that?
If at all possible, the server-side is a better choice for generating PDFs. It's probably going to be faster for most users and returning a file via standard HTTP request is much more robust than the current client-side options.
That said, this library will generate a PDF on the client-side: http://snapshotmedia.co.uk/blog/jspdf
In browsers that support data URIs, it can return the PDF directly. In other browsers, you can couple it with a Flash component called Downloadify to accomplish the same.