Ruby Requires Chilkat v11.7.0+

Search for Text in a PDF

See more PDF Text Extraction Examples

Demonstrates the "search" operation, which finds every occurrence of a string in a PDF and returns each match with its page number and the text around it. Matching ignores case unless caseSensitive is true. Ruby

require 'chilkat'

success = false

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

#  The three-page PDF used in this example is available at search_context.pdf

pdf = Chilkat::CkPdf.new()
success = pdf.LoadFile("qa_data/pdf/search_context.pdf")
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

json = Chilkat::CkJsonObject.new()
jsonOut = Chilkat::CkJsonObject.new()

#  The string to find.
json.UpdateString("query","chilkat")

#  The number of characters returned before and after each match.  The default is 40.
json.UpdateInt("context",30)

success = pdf.ExtractText("search",json,jsonOut)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

#  "count" is the number of matches.  Each match has the page, the matched text as it appears
#  in the PDF, and the text before and after it.
print "Matches: " + jsonOut.IntOf("count").to_s() + "\n";

i = 0
count_i = jsonOut.SizeOfArray("matches")
while i < count_i
    jsonOut.put_I(i)
    print "page " + jsonOut.IntOf("matches[i].page").to_s() + ": ..." + jsonOut.stringOf("matches[i].before") + "[" + jsonOut.stringOf("matches[i].text") + "]" + jsonOut.stringOf("matches[i].after") + 
        "..." + "\n";
    i = i + 1
end

#  The search ignores case by default.  Set caseSensitive to find only the exact spelling.
json.UpdateBool("caseSensitive",true)
json.UpdateString("query","Chilkat")
success = pdf.ExtractText("search",json,jsonOut)
if (success == false)
    print pdf.lastErrorText() + "\n";
    exit
end

print "Case-sensitive matches for Chilkat: " + jsonOut.IntOf("count").to_s() + "\n";

#  Sample output:

#  Matches: 5
#  page 1: ...[Chilkat] River Field Notes The Chilkat...
#  page 1: ...Chilkat River Field Notes The [Chilkat] River runs for about fifty mi...
#  page 2: ...DAY ONE: UPPER [CHILKAT] FLATS Clear and cold, minus e...
#  page 2: ...he river is sometimes spelled [chilkat] in older records, and the val...
#  page 3: ...y because the fish run on the [Chilkat] was thinning. Two tagged bird...
#  Case-sensitive matches for Chilkat: 3