PowerShell Requires Chilkat v11.7.0+

Get Every Occurrence of a Label in a PDF

See more PDF Text Extraction Examples

Demonstrates the "labelOccurrence" option. When the same label appears more than once (for example "Total:" on each of several receipts), "first" (the default) uses the first occurrence, "all" returns every occurrence with its page, and a number selects one occurrence. PowerShell

Add-Type -Path "C:\chilkat\ChilkatDotNet47-x64\ChilkatDotNet47.dll"

$success = $false

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

#  The PDF used in this example (three receipts, one per page) is available at three_receipts.pdf

$pdf = New-Object Chilkat.Pdf
$success = $pdf.LoadFile("qa_data/pdf/three_receipts.pdf")
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$json = New-Object Chilkat.JsonObject
$jsonOut = New-Object Chilkat.JsonObject

#  Each of the three pages is a receipt with a "Total:" line.
$json.UpdateString("label","Total")
$json.UpdateString("labelValue","right")

#  By default only the first occurrence (in reading order) is used.
$success = $pdf.ExtractText("text",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("First total: " + $jsonOut.StringOf("text"))

#  labelOccurrence "all" returns every occurrence.  The "text" member holds the values joined
#  by line breaks, and labelMatches has one entry per occurrence with its page.
$json.UpdateString("labelOccurrence","all")
$success = $pdf.ExtractText("text",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$i = 0
$count_i = $jsonOut.SizeOfArray("labelMatches")
while ($i -lt $count_i) {
    $jsonOut.I = $i
    $("Page " + $jsonOut.IntOf("labelMatches[i].page") + " total: " + $jsonOut.StringOf("labelMatches[i].text"))
    $i = $i + 1
}

#  A number selects one occurrence: 2 is the second.
$json.UpdateInt("labelOccurrence",2)
$success = $pdf.ExtractText("text",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("Second total: " + $jsonOut.StringOf("text"))

#  The occurrences are counted over the selected pages, so combining "pages" with the label
#  is another way to pick one receipt:
$json.UpdateString("labelOccurrence","first")
$json.UpdateString("pages","3")
$json.UpdateString("label","Receipt No.")
$success = $pdf.ExtractText("text",$json,$jsonOut)
if ($success -eq $false) {
    $($pdf.LastErrorText)
    exit
}

$("Receipt number on page 3: " + $jsonOut.StringOf("text"))

#  Sample output:

#  First total: $19.86
#  Page 1 total: $19.86
#  Page 2 total: $17.34
#  Page 3 total: $23.62
#  Second total: $17.34
#  Receipt number on page 3: 1003