GetOCGZoomMin Method (GdPicturePDF)

In This Topic

Returns 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 GetOCGZoomMin( _

   ByVal OCGId As Integer _

) As Double

public double GetOCGZoomMin( 

   int OCGId

)

public function GetOCGZoomMin( 

    OCGId: Integer

): Double;

public function GetOCGZoomMin( 

   OCGId : int

) : double;

public: double GetOCGZoomMin( 

   int OCGId

)

public:

double GetOCGZoomMin( 

   int OCGId

)

Parameters

OCGId: The unique identifier of the required OCG entry. You can obtain this identifier using the GdPicturePDF.GetOCG method.

Return Value

The minimum recommended magnification factor at which the content of the specified OCG is best viewed. The GdPicturePDF.GetStat method can be subsequently used to determine if this method has been successful.

Remarks

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

It is recommend to use the GdPicturePDF.GetStat method to identify the specific reason for the method's failure, if any.

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 find out the range of magnifications of the specified layer in the PDF document.

VB.NET
C#

Dim gdpicturePDF As New GdPicturePDF()

Dim status As GdPictureStatus = gdpicturePDF.LoadFromFile("test.pdf", False)

If status = GdPictureStatus.OK Then

    Dim output As String = ""

    Dim ocgCount As Integer = gdpicturePDF.GetOCGCount()

    status = gdpicturePDF.GetStat()

    If status = GdPictureStatus.OK Then

        output = "The number of OCG layers: " + ocgCount.ToString()

        Dim OcgId As Integer = 0

        Dim title As String = ""

        Dim onOff As Boolean = False

        Dim zoom As Double = 0

        For i As Integer = 0 To ocgCount - 1

            output = output + vbCrLf + "Layer nr." + (i + 1).ToString() + ": "

            OcgId = gdpicturePDF.GetOCG(i)

            status = gdpicturePDF.GetStat()

            If status = GdPictureStatus.OK Then

                title = gdpicturePDF.GetOCGTitle(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + "Title = " + title.ToString()

                Else

                    output = output + "Title = Error (" + status.ToString() + ")"

                End If

            

                onOff = gdpicturePDF.GetOCGIntentView(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    If onOff Then

                        output = output + "    Intent = View"

                    Else

                        output = output + "    Intent = Design"

                    End If

                Else

                    output = output + "    Intent = Error (" + status.ToString() + ")"

                End If

            

                zoom = gdpicturePDF.GetOCGZoomMin(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + vbCrLf + "       zoomMin = " + String.Format("{0:0.00}", zoom)

                Else

                    output = output + vbCrLf + "       zoomMin = Error (" + status.ToString() + ")"

                End If

            

                zoom = gdpicturePDF.GetOCGZoomMax(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + "    zoomMax = " + String.Format("{0:0.00}", zoom)

                Else

                    output = output + "    zoomMax = Error (" + status.ToString() + ")"

                End If

            Else

                output = output + "The GetOCG() method has failed with the status: " + status.ToString()

            End If

        Next

        MessageBox.Show(output, "Example: GetOCGZoomMin")

    Else

        MessageBox.Show("The GetOCGCount() method has failed with the status: " + status.ToString(), "Example: GetOCGZoomMin")

    End If

Else

    MessageBox.Show("The file can't be loaded.", "Example: GetOCGZoomMin")

End If

gdpicturePDF.Dispose()

GdPicturePDF gdpicturePDF = new GdPicturePDF();

GdPictureStatus status = gdpicturePDF.LoadFromFile("test.pdf", false);

if (status == GdPictureStatus.OK)

{

    string output = "";

    int ocgCount = gdpicturePDF.GetOCGCount();

    status = gdpicturePDF.GetStat();

    if (status == GdPictureStatus.OK)

    {

        output = "The number of OCG layers: " + ocgCount.ToString();

        int OcgId = 0;

        string title = "";

        bool onOff = false;

        double zoom = 0;

        for (int i = 0; i < ocgCount; i++)

        {

            output = output + "\nLayer nr." + (i+1).ToString() + ": ";

            OcgId = gdpicturePDF.GetOCG(i);

            status = gdpicturePDF.GetStat();

            if (status == GdPictureStatus.OK)

            {

                title = gdpicturePDF.GetOCGTitle(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + "Title = " + title.ToString();

                else

                    output = output + "Title = Error (" + status.ToString() + ")";

            

                onOff = gdpicturePDF.GetOCGIntentView(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                {

                    if (onOff)

                        output = output + "    Intent = View";

                    else

                        output = output + "    Intent = Design";

                }

                else

                    output = output + "    Intent = Error (" + status.ToString() + ")";

            

                zoom = gdpicturePDF.GetOCGZoomMin(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + "\n       zoomMin = " + string.Format("{0:0.00}", zoom);

                else

                    output = output + "\n       zoomMin = Error (" + status.ToString() + ")";

            

                zoom = gdpicturePDF.GetOCGZoomMax(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + "    zoomMax = " + string.Format("{0:0.00}", zoom);

                else

                    output = output + "    zoomMax = Error (" + status.ToString() + ")";

            }

            else

                output = output + "The GetOCG() method has failed with the status: " + status.ToString();

        }

        MessageBox.Show(output, "Example: GetOCGZoomMin");

    }

    else

    {

        MessageBox.Show("The GetOCGCount() method has failed with the status: " + status.ToString(), "Example: GetOCGZoomMin");

    }

}

else

{

    MessageBox.Show("The file can't be loaded.", "Example: GetOCGZoomMin");

}

gdpicturePDF.Dispose();

Reference

GdPicturePDF Class
GdPicturePDF Members
GetOCGCount Method
GetOCG Method
GetOCGTitle Method
GetOCGIntentView Method
GetOCGZoomMax Method
NewOCG Method