Get Page Info

This guide shows you how to get info about a page(s) in a PDF. The sample output contains information about the page, including its rotation, media box, height and width.

Sample input #

This example accepts an input path to the PDF and an optional page number to get its info.

Before you begin #

You should get your API key from your UniCloud account.

If this is your first time using UniPDF SDK, follow our instructions to set up a local development environment[add a link to the getting started guide].

Project setup #

Clone the project repository #

In your terminal, clone the examples repository. It contains the Go code we will be using for this guide.

git clone https://github.com/unidoc/unipdf-examples.git

Change into the repository directory and navigate to the pages folder.

cd unipdf-examples/pages

Configure environment variables #

Replace the UNIDOC_LICENSE_API_KEY with your API credentials from your UniCloud account.

Linux/Mac #

export UNIDOC_LICENSE_API_KEY=PUT_YOUR_API_KEY_HERE

Windows #

set UNIDOC_LICENSE_API_KEY=PUT_YOUR_API_KEY_HERE

How it works #

Lines 10-18 import the UniPDF packages and other required dependencies.

Lines 20-27 authenticate your request with your UNIDOC_LICENSE_API_KEY with the init function.

The main function in lines 29-55 accepts at least one argument: an input path to the PDF and an optional page number to get its info. The main function passes the arguments as input to the printPdfPageProperties function.

Lines 57-95 create the printPdfPageProperties function. It reads each page from the PDF, if no page number was provided and output its properties to the terminal.

Run the code #

Run this command to get page(s) info about the PDF. This will also get all the required dependencies to run the program.

go run pdf_page_info.go path_to_file.pdf [optional page number]  

Sample output #

The page info for the specified page or all pages in the PDF will be displayed on the terminal. You should get something similar to this.

# these values are in point(the SI unit in UniPDF)
Page rotation: 0

Page mediabox: &{Llx:0 Lly:0 Urx:612 Ury:792}

Page height: 792.000000

Page width: 612.000000