Is there a way to determine XPATH from an XML file and offset position?

[Kelly Dolan]

I'm in a strange situation. I have an XML document. I hand the XML document as a string to a "black box" that evaluates the content and returns a list of findings. I next display the XML document (using XSL) along w/ the findings. On click of a finding, I need to scroll to the corresponding location in the document.

The core business logic for the display currently supports scroll to given an XPATH and offset (the offset I believe being the number of characters w/in the element identified by the XPATH). Each finding corresponds with some location w/in the XML content (PCDATA) but the locations are represented as the character offset from the beginning of the XML as a string. The locations take into consideration the XML declaration, comments, PIs, etc.

One approach is to convert a fixed location w/in an XML string to an XPATH and offset w/in an element. Does anyone know if there is a library or function that exists that does this? This is not something I care to implement. I have a Plan B if not.

Thanks!
Kelly