The question recently came up during a discussion with a friend of how (if at all) you
can unambiguously determine, programmatically, with JavaScript, what page of a PDF document
the user is looking at when a widget is tripped. This becomes an interesting (and important)
issue when the complexities of template-spawning are overlaid, so to speak, on the
discussion. Suppose the user has spawned 15 template pages, then backtracked through half of
them. He clicks into a text field. What page is he on?
Well, if it’s a spawned page, all the field names begin with ‘P’ plus the zero-based page number. But more generally, you can find the current page number by just doing:
var currentPage = this.pageNum;
Again, though, remember that the page numbering is zero-based (like arrays in C). The first page of any document is zero.