Page Count

The page count sits in a document’s extended app properties, written there by whatever editor last saved the file. AppProperties.Pages reads it back.

doc, err := document.Open("document.docx")
if err != nil {
    log.Fatalf("error opening document: %s", err)
}
defer doc.Close()

fmt.Println("Pages:", doc.AppProperties.Pages())

The value is an int32, and it is 0 when the property is absent.

It is metadata, not a measurement

UniOffice does not lay a document out into pages, so it has nothing to count. What Pages returns is what the producing application recorded at save time. Two consequences follow.

A document created with document.New() reports 0, however much content you add to it, because no editor has ever paginated it. That is stated in the godoc and is not a bug to work around.

A document opened, edited and saved with UniOffice keeps whatever count it arrived with. Delete half the content and the number does not change. AppProperties.SetPages will write a different value, but it writes whatever you pass without checking it, so it is a way to record a count you obtained elsewhere rather than a way to compute one.

Getting a real count

The field approach hands the problem to Word or LibreOffice, which do paginate. The PDF approach gives your program a number, at the cost of running the conversion; see Convert a document to PDF.

Run the example

The example opens the document.docx fixture in its own directory and prints its page count, then prints the count of a freshly created document to show the difference.

git clone https://github.com/unidoc/unioffice-examples.git
cd unioffice-examples/document/number-of-pages
go run main.go

If this is your first time using UniOffice, follow the getting started guide to create an API key and set up your development environment.