Lua Requires Chilkat v11.7.0+

Extract One Section of a PDF by its Heading

See more PDF Text Extraction Examples

Demonstrates "labelValue": "section", which returns everything from a heading up to the next heading of the same or higher level. With the "markdown" operation the section keeps its own sub-headings. Lua

local chilkat = require("chilkat")

-- This example requires the Chilkat API to have been previously unlocked.
-- See Global Unlock Sample for sample code.

-- The PDF used in this example is available at sectioned_doc.pdf

local pdf = chilkat.Pdf.new()
local success = pdf:load_file("qa_data/pdf/sectioned_doc.pdf")
if not success then
    print(pdf.last_error_text)
    return
end

local json = chilkat.JsonObject.new()
local jsonOut = chilkat.JsonObject.new()

-- The document has the sections Introduction, Opening Hours, Terms and Conditions (with the
-- sub-sections Admission, Safety and Liability) and Contact.  Get the Terms and Conditions:
-- everything after that heading up to the next heading of the same level (Contact).  The heading
-- itself is not part of the value; labelMatches[0].label has it.
json:update_string("label", "Terms and Conditions")
json:update_string("labelValue", "section")

success = pdf:extract_text("markdown", json, jsonOut)
if not success then
    print(pdf.last_error_text)
    return
end

print(jsonOut:string_of("markdown"))

-- The same with the "text" operation gives the section as plain text.
success = pdf:extract_text("text", json, jsonOut)
if not success then
    print(pdf.last_error_text)
    return
end

print("---- as text ----")
print(jsonOut:string_of("text"))

-- Sample output:

-- ### Admission
--
-- Admission is free. Groups of more than ten should book in advance so that a volunteer can be assigned to them.
--
-- ### Safety
--
-- No more than eight people may be on the stair at one time. Children under twelve must be accompanied by an adult, and the lantern room is closed in high winds.
--
-- ### Liability
--
-- Visitors climb the tower at their own risk. The society carries public liability insurance but accepts no responsibility for personal property.
-- ---- as text ----
-- Admission
--
-- Admission is free. Groups of more than ten should book in advance so that a volunteer can be assigned to them.
--
-- Safety
--
-- No more than eight people may be on the stair at one time. Children under twelve must be accompanied by an adult, and the lantern room is closed in high winds.
--
-- Liability
--
-- Visitors climb the tower at their own risk. The society carries public liability insurance but accepts no responsibility for personal property.