SetOCGZoomMin Method (GdPicturePDF)

In This Topic

Sets up the minimum magnification factor of an optional content group, specified by its unique identifier.

It is the minimum value of a defined range of magnifications at which the content of this optional content group is best viewed.

Syntax

Visual Basic
C#
Delphi
JScript
Managed Extensions for C++
C++/CLI

'Declaration
 
Public Function SetOCGZoomMin( _
   ByVal OCGId As Integer, _
   ByVal ZoomMin As Single _
) As GdPictureStatus

public GdPictureStatus SetOCGZoomMin( 
   int OCGId,
   float ZoomMin
)

public function SetOCGZoomMin( 
    OCGId: Integer;
    ZoomMin: Single
): GdPictureStatus;

public function SetOCGZoomMin( 
   OCGId : int,
   ZoomMin : float
) : GdPictureStatus;

public: GdPictureStatus SetOCGZoomMin( 
   int OCGId,
   float ZoomMin
)

public:
GdPictureStatus SetOCGZoomMin( 
   int OCGId,
   float ZoomMin
)

Parameters

OCGId: The unique identifier of the required OCG entry. You can obtain this identifier using the GdPicturePDF.GetOCG method.
ZoomMin: The new value of the minimum magnification factor to be set. Please use the value 0.1 to define the 10% or 1 to define the 100% zoom factor.

Return Value

A member of the GdPictureStatus enumeration. If the method has been successfully followed, then the return value is GdPictureStatus.OK.

We strongly recommend always checking this status first.

Remarks

This method is only allowed for use with non-encrypted documents.

To define the 10% to 200% zoom range, please set the ZoomMin parameter to 0.1 using the GdPicturePDF.SetOCGZoomMin method and the ZoomMax parameter to 2 using the GdPicturePDF.SetOCGZoomMax method.

Be aware that some viewers can interpret this value as the minimum value of a defined range of magnifications below which the content of this optional content group is viewed, meaning that when zooming lower the content will not display.

Example

How to change the range of magnifications for the specified layer in the PDF document. The layer in this example is best viewed (in some viewers it is only viewed) when zooming between 0% and 100%.

VB.NET
C#

Dim caption As String = "Example: SetOCGZoomMin"
Dim gdpicturePDF As New GdPicturePDF()
'Please see the example of the SetImageOptional() method for the test_ImageLayer.pdf file.
If gdpicturePDF.LoadFromFile("test_ImageLayer.pdf", False) = GdPictureStatus.OK Then
    Dim ocgCount As Integer = gdpicturePDF.GetOCGCount()
    Dim status As GdPictureStatus = gdpicturePDF.GetStat()
    If (status = GdPictureStatus.OK) AndAlso (ocgCount > 0) Then
        Dim ocgID As Integer = gdpicturePDF.GetOCG(0)
        status = gdpicturePDF.GetStat()
        If status = GdPictureStatus.OK Then
            If (gdpicturePDF.SetOCGTitle(ocgID, "Updated layer") = GdPictureStatus.OK) AndAlso
               (gdpicturePDF.SetOCGLockedState(ocgID, False) = GdPictureStatus.OK) AndAlso
               (gdpicturePDF.SetOCGZoomMin(ocgID, 0) = GdPictureStatus.OK) AndAlso
               (gdpicturePDF.SetOCGZoomMax(ocgID, 1) = GdPictureStatus.OK) Then
                If gdpicturePDF.SaveToFile("test_UpdatedLayer.pdf") = GdPictureStatus.OK Then
                    MessageBox.Show("The example HAS been followed successfully and the file has been saved.", caption)
                Else
                    MessageBox.Show("The example HAS been followed successfully, but the file can't be saved. Status: " + gdpicturePDF.GetStat().ToString(), caption)
                End If
            Else
                MessageBox.Show("Setting up layer's options has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption)
            End If
        Else
            MessageBox.Show("The GetOCG() method has failed with the status: " + status.ToString(), caption)
        End If
    Else
        MessageBox.Show("The GetOCGCount() method has failed with the status: " + status.ToString(), caption)
    End If
Else
    MessageBox.Show("The file can't be loaded.", caption)
End If
gdpicturePDF.Dispose()

string caption = "Example: SetOCGZoomMin";
GdPicturePDF gdpicturePDF = new GdPicturePDF();
//Please see the example of the SetImageOptional() method for the test_ImageLayer.pdf file.
if (gdpicturePDF.LoadFromFile("test_ImageLayer.pdf", false) == GdPictureStatus.OK)
{
    int ocgCount = gdpicturePDF.GetOCGCount();
    GdPictureStatus status = gdpicturePDF.GetStat();
    if ((status == GdPictureStatus.OK) && (ocgCount > 0))
    {
        int ocgID = gdpicturePDF.GetOCG(0);
        status = gdpicturePDF.GetStat();
        if (status == GdPictureStatus.OK)
        {
            if ((gdpicturePDF.SetOCGTitle(ocgID, "Updated layer") == GdPictureStatus.OK) &&
                (gdpicturePDF.SetOCGLockedState(ocgID, false) == GdPictureStatus.OK) &&
                (gdpicturePDF.SetOCGZoomMin(ocgID, 0) == GdPictureStatus.OK) &&
                (gdpicturePDF.SetOCGZoomMax(ocgID, 1) == GdPictureStatus.OK))
            {
                if (gdpicturePDF.SaveToFile("test_UpdatedLayer.pdf") == GdPictureStatus.OK)
                {
                    MessageBox.Show("The example HAS been followed successfully and the file has been saved.", caption);
                }
                else
                {
                    MessageBox.Show("The example HAS been followed successfully, but the file can't be saved. Status: " + gdpicturePDF.GetStat().ToString(), caption);
                }
            }
            else
            {
                MessageBox.Show("Setting up layer's options has failed with the status: " + gdpicturePDF.GetStat().ToString(), caption);
            }
        }
        else
        {
            MessageBox.Show("The GetOCG() method has failed with the status: " + status.ToString(), caption);
        }
    }
    else
    {
        MessageBox.Show("The GetOCGCount() method has failed with the status: " + status.ToString(), caption);
    }
}
else
{
    MessageBox.Show("The file can't be loaded.", caption);
}
gdpicturePDF.Dispose();

Reference

GdPicturePDF Class
GdPicturePDF Members
GetOCGCount Method
GetOCG Method
SetOCGTitle Method
SetOCGExportState Method
SetOCGLockedState Method
SetOCGPrintState Method
SetOCGViewState Method
SetOCGZoomMax Method