VB.NET Requires Chilkat v11.7.0+

Why a PDF Optimization Was Skipped

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Demonstrates the "skipped" array, which lists the options that were asked for but not applied, each with a reason and, where it is page-specific, the pages. An option is skipped when it is reserved for a later release (mergeFontSubsets, compactType1Fonts), when the rules of the file forbid it (objectStreams in a PDF/A-1 file), or when the content could not be parsed safely (tidyContent and coalesceContent on a page whose content stream the parser does not understand). Nothing is ever changed on a guess: an option that cannot be applied safely is skipped and reported. VB.NET

Dim success As Boolean = 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 is available at grand_canyon_hiking_guide.pdf

Dim pdf As New Chilkat.Pdf
success = pdf.LoadFile("qa_data/pdf/grand_canyon_hiking_guide.pdf")
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


'  Ask for the two options that are reserved for a later release.
Dim json As New Chilkat.JsonObject
json.UpdateBool("mergeFontSubsets",True)
json.UpdateBool("compactType1Fonts",True)

Dim jsonOut As New Chilkat.JsonObject
success = pdf.Optimize("audit",json,jsonOut)
If (success = False) Then
    Debug.WriteLine(pdf.LastErrorText)
    Exit Sub
End If


Dim i As Integer = 0
Dim numSkipped As Integer = jsonOut.SizeOfArray("skipped")
Debug.WriteLine("skipped: " & numSkipped)
While i < numSkipped
    jsonOut.I = i
    Debug.WriteLine("   " & jsonOut.StringOf("skipped[i].option") & " - " & jsonOut.StringOf("skipped[i].reason"))
    i = i + 1
End While

'  A skipped option is not a failure: Optimize returns true, the other options are applied, and the
'  report says exactly what was left undone.