Fill Form Fields
This guide will show you how to enter values for the form fields in a PDF document by using data in JSON format. The output PDF is a filled and flattened form whose content cannot be edited.
You can also fill forms with custom font using data from a JSON input file.
Sample input
This snippet will fill form fields named full_name
with the value Roy M. Ferrell
amd address-line_1
with the value Lane 3, Felicity Avenue, Sesch
.
[
{
"name": "full_name",
"value": "Roy M. Ferrell"
},
{
"name": "address_line_1",
"value": "Lane 3, Felicity Avenue, Sesch"
},
...
]
Before you begin
You should get your API key from your UniCloud account.
If you are using the UniPDF SDK for the first time, follow this guide to set up a local development environment.
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
Navigate to the forms
folder in the unipdf-examples directory.
cd unipdf-examples/forms
How it works
Lines 9-17
import the UniPDF packages and other required dependencies.
The init function Lines 19-26
authenticate your request with your UNIDOC_LICENSE_API_KEY
.
The main function in lines 29-78
validates your input and passes them as arguments to the fillFields
function.
Lines 82-138
define the fillFields
function, which takes inputPath
, jsonPath
, and outputPath
as parameters. The function gets the form field data and values from the jsonPath
, uses them to fill the form in the inputPath
, and then saves the flattened form to the outputPath
.
Run the code
Run this command to fill a PDF form with a JSON input file. This will also install the required dependencies to run the program.
go run pdf_form_fill_json.go input.pdf fill.json output.pdf