I have some XML files which are used to generate my webpages, however I need to be able to allow the user to select a number of pages then combine them into one PDF. This PDF needs to have different styling to the actual web page (the content is kept in XML files ;) ).
p.s. the PDF must have table of contents... and will include images taken from the website.
You would use a library like iText or iTextSharp to build a PDF using your content.
Write an XSLT stylesheet which transforms your XML files to XSL-FO and then use an XSL-FO implementation (e.g. Apache FOP) to produce PDF.
I use Prince in my product. It's not cheap (neither is my product), but it's extremely easy to use, and very fast.
来源：https://stackoverflow.com/questions/2622949/multiple-xmls-to-pdf-best-approach