Example





In This Topic
GdPicture14 Namespace / GdPicturePDF Class / GetOCGCount Method

GetOCGCount Method (GdPicturePDF)

In This Topic
Returns the number of the optional content group (OCG) entries defined in the currently loaded PDF document.

Optional Content Groups, also knows as Layers, are a very effective tool to control the visibility of the page content, that can be selectively viewed or hidden, by users or viewers.

Syntax
'Declaration

 


Public Function GetOCGCount() As Integer
public int GetOCGCount()
public function GetOCGCount(): Integer; 
public function GetOCGCount() : int;
public: int GetOCGCount(); 
public:

int GetOCGCount();

Return Value

The number of OCG entries (layers) defined in the document. The 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 GetStat method to identify the specific reason for the method's failure, if any.

Example
How to find out the number of layers defined in the PDF document and enumerate them subsequently. 
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 state As PdfOcgState = PdfOcgState.Undefined

        Dim onOff As Boolean = False

        For i As Integer = 0 To ocgCount - 1

            output = output + vbCrLf + "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

            

                state = gdpicturePDF.GetOCGViewState(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + " ; View = " + state.ToString()

                Else

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

                End If

            

                state = gdpicturePDF.GetOCGExportState(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + " ; Export = " + state.ToString()

                Else

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

                End If

            

                state = gdpicturePDF.GetOCGPrintState(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + " ; Print = " + state.ToString()

                Else

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

                End If

            

                onOff = gdpicturePDF.GetOCGLockedState(OcgId)

                status = gdpicturePDF.GetStat()

                If status = GdPictureStatus.OK Then

                    output = output + " ; Locked = " + onOff.ToString()

                Else

                    output = output + " ; Locked = 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: GetOCGCount")

    Else

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

    End If

Else

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

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 = "";

        PdfOcgState state = PdfOcgState.Undefined;

        bool onOff = false;

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

        {

            output = output + "\nNr." + (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() + ")";

            

                state = gdpicturePDF.GetOCGViewState(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + " ; View = " + state.ToString();

                else

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

            

                state = gdpicturePDF.GetOCGExportState(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + " ; Export = " + state.ToString();

                else

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

            

                state = gdpicturePDF.GetOCGPrintState(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + " ; Print = " + state.ToString();

                else

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

            

                onOff = gdpicturePDF.GetOCGLockedState(OcgId);

                status = gdpicturePDF.GetStat();

                if (status == GdPictureStatus.OK)

                    output = output + " ; Locked = " + onOff.ToString();

                else

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

            }

            else

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

        }

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

    }

    else

    {

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

    }

}

else

{

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

}

gdpicturePDF.Dispose();
See Also

Reference

GdPicturePDF Class
GdPicturePDF Members
GetOCG Method
GetOCGTitle Method
GetOCGExportState Method
GetOCGLockedState Method
GetOCGPrintState Method
GetOCGViewState Method