Using VB.NET PDF SDK
VB.NET PDF: how to format PDF Document

Dim inputFilePath As String = "C:\1.pdf"

' Opne file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Get viewer preferences from the document.
Dim vp As PDFViewerPreferences = doc.GetViewerPreferences()
If vp IsNot Nothing Then
    Console.WriteLine("Hide Toolbar:              {0}", vp.HideToolbar)
    Console.WriteLine("Hide Menubar:              {0}", vp.HideMenubar)
    Console.WriteLine("Hide Window UI:            {0}", vp.HideWindowUI)
    Console.WriteLine("Fit Window:                {0}", vp.FitWindow)
    Console.WriteLine("Center Window:             {0}", vp.CenterWindow)
    Console.WriteLine("Display Doc Title:         {0}", vp.DisplayDocTitle)
    Console.WriteLine("Non Full Screen Page Mode: {0}", vp.NonFullScreenPageMode)
    Dim direction As String = "L2R"
    If vp.IsDirectionR2L Then
        direction = "R2L"
    End If
    Console.WriteLine("Direction:                 {0}", direction)
    Console.WriteLine("View Area:                 {0}", vp.ViewArea)
    Console.WriteLine("View Clip:                 {0}", vp.ViewClip)
    Console.WriteLine("Print Area:                {0}", vp.PrintArea)
    Console.WriteLine("Print Clip:                {0}", vp.PrintClip)
    Console.WriteLine("Use Current Print Scaling: {0}", vp.UsePrintScaling)
    Console.WriteLine("Duplex:                    {0}", vp.Duplex)
    Console.WriteLine("Checkbox in the print dialog associated with input paper tray is checked: {0}", vp.PickTrayByPDFSize)
    Console.WriteLine("Print Page Range:          {0}", vp.GetPrintPageRangeString())
    Console.WriteLine("Number of Copies:          {0}", vp.NumCopies)
Else
    Console.WriteLine("No ViewerPreferences entry in the document.")
End If

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)

' Initial a New viewer preferences with default settings.
Dim vp As PDFViewerPreferences = New PDFViewerPreferences()
' Hide toolbar when the document Is open.
vp.HideToolbar = True
' Hide menubar when the document Is open.
vp.HideMenubar = True
' Set default print area to MediaBox.
vp.PrintArea = PDFPageBoundaryType.MediaBox
' Set the default print copies to 3 in the print dialog.
vp.NumCopies = 3
' Update the Viewer Preferences
doc.SetViewerPreferences(vp)

' Save file
doc.Save(outputFilePath)

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Remove Viewer Preferences in the document. 
doc.SetViewerPreferences(Nothing)
' Save file
doc.Save(outputFilePath)

Dim inputFilePath As String = "C:\1.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Get page layout setting
Dim pageLayout As PDFPageLayout = doc.GetPageLayout()
' Valid Values:
' SinglePage, OneColumn, TwoColumnLeft, TwoColumnRight, TwoPageLeft, TwoPageRight
Console.WriteLine("Page Layout: {0}", pageLayout.ToString())

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Display pages in 2 columns with odd numbered pages on the left.
doc.SetPageLayout(PDFPageLayout.TwoColumnLeft)
' Save file
doc.Save(outputFilePath)

Dim inputFilePath As String = "C:\1.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Get page mode setting
Dim pageMode As PDFPageMode = doc.GetPageMode()
' Valid Values:
' UseNone, UseOutlines, UseThumbs, FullScreen, UseOC, UseAttachments
Console.WriteLine("Page Mode: {0}", pageMode.ToString())

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Show page in Full-screen mode.
doc.SetPageMode(PDFPageMode.FullScreen)
' Save file
doc.Save(outputFilePath)

Dim inputFilePath As String = "C:\1.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)

' Get Open Action from the document, the return Is a PDF destination.
Dim op As PDFDestination = doc.GetOpenActionDestination()
If op IsNot Nothing Then
    Console.WriteLine("Mode: {0}; Page Index: {1}", op.Mode, op.PageIdx)
Else
    Console.WriteLine("No OpenAction")
End If

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Create a /FitB destination for the Open Action, which would show the 2nd page when open the document.
Dim op As PDFDestination = PDFDestination.CreateFitB(1)
' Update open action setting
doc.SetOpenActionDestination(op)
' Save file
doc.Save(outputFilePath)

Dim inputFilePath As String = "C:\1.pdf"
Dim outputFilePath As String = "C:\output.pdf"

' Open file
Dim doc As PDFDocument = New PDFDocument(inputFilePath)
' Create a /XYZ destination for the Open Action with zoom Is 200% And top-left point Is [0,0].
Dim pageIndex As Integer = 1
Dim startPoint As PointF = New PointF(0, 0)
Dim zoom As Double = 2.0
Dim op As PDFDestination = PDFDestination.CreateXYZ(pageIndex, startPoint.X, startPoint.Y, zoom)
' Update open action setting
doc.SetOpenActionDestination(op)
' Save file
doc.Save(outputFilePath)