pdf-inspection

name	pdf-inspection
description	Techniques for inspecting PDF form fields and their properties using Python libraries like pypdf.

PDF Inspection Skill

This skill covers how to identify and list form fields in a PDF document using the pypdf library.

Prerequisites

• Python 3.x
• pypdf library (pip install pypdf)

Usage Patterns

Listing All Fields

To list all fields and their types:

import pypdf

def list_pdf_fields(file_path):
    reader = pypdf.PdfReader(file_path)
    fields = reader.get_fields()
    if not fields:
        print("No fields found.")
        return
    
    for name, field in fields.items():
        field_type = field.get("/FT")
        print(f"Field Name: {name}, Type: {field_type}")

list_pdf_fields("document.pdf")

Understanding Field Types

• /Tx: Text field
• /Btn: Button (checkbox or radio button)
• /Ch: Choice field (dropdown or list box)
• /Sig: Signature field

Identifying Checkbox Values

Checkboxes often use "Off" and another value (like "Yes" or "On"). You can find these in the /AP or /V keys if they have a value.

field_props = reader.get_fields()["field_name"]
print(field_props.get("/V")) # Current value