There is an excellent discussion of using an Ifilter to get the text out of a PDF document here
but my problem is a bit different.
I want to extract the text of a pdf that has been downloaded in a browser (IE, Twebbrowser) but I want to know
a) when that download is complete .. can I use OnDocumentComplete or does that only work for the HTML pages
b) where the pdf is , so I can examine it. I suppose it is in a cache somewhere, but how can I find it/establish the correspondence between the original pdf url and the name in the cache?