PdfGetMetadata Method (GdViewer)

In This Topic

Returns the metadata of the currently displayed PDF document, if any are stored in the PDF. If the document currently displayed in the GdViewer control is not the PDF file, the method will fail.

Syntax

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

'Declaration
 
Public Function PdfGetMetadata() As String

public string PdfGetMetadata()

public function PdfGetMetadata(): String;

public function PdfGetMetadata() : String;

public: string* PdfGetMetadata();

public:
String^ PdfGetMetadata();

Return Value

The value of the document's metadata as a string in the XML format. The GetStat method can be subsequently used to determine if this method has been successful.

Remarks

This method is only meaningful for PDF documents, otherwise it returns an empty string. It is recommend to use the GetStat method to identify the specific reason for the method's failure, if any.

Example

How to retrieve the PDF metadata associated with the loaded PDF document.

VB.NET
C#

'We assume that the GdViewer1 control has been properly integrated.
If GdViewer1.DisplayFromFile("") = GdPictureStatus.OK Then
    Dim filename As String = GdViewer1.GetLastPath()
    Dim message As String = "The current file is: " + filename
    If GdViewer1.GetDocumentType() = DocumentType.DocumentTypePDF Then
        message += vbCrLf + "PDF Version: " + GdViewer1.PdfGetVersion() +
                   vbCrLf + "Keywords: " + GdViewer1.PdfGetKeywords()
        'Retrieving the PDF metadata.
        Dim metadata As String = GdViewer1.PdfGetMetadata()
        If GdViewer1.GetStat() = GdPictureStatus.OK Then
            Dim metadataFile As String = filename.Replace(".pdf", "_metadata.xmp")
            System.IO.File.WriteAllText(metadataFile, metadata)
            message += vbCrLf + "Metadata has been successfully saved. File: " + metadataFile
        Else
            message += vbCrLf + "Metadata has not been retrieved. Status: " + GdViewer1.GetStat().ToString()
        End If
    Else
        message += vbCrLf + "This file is not a PDF document, its format is: " + GdViewer1.GetDocumentType().ToString()
    End If
            
    MessageBox.Show(message, "GdViewer.PdfGetMetadata")
Else
    MessageBox.Show("The file can't be loaded. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.PdfGetMetadata")
End If

//We assume that the GdViewer1 control has been properly integrated.
if (GdViewer1.DisplayFromFile("") == GdPictureStatus.OK)
{
    string filename = GdViewer1.GetLastPath();
    string message = "The current file is: " + filename;
    if (GdViewer1.GetDocumentType() == DocumentType.DocumentTypePDF)
    {
        message += "\nPDF Version: " + GdViewer1.PdfGetVersion() +
                   "\nKeywords: " + GdViewer1.PdfGetKeywords();
        //Retrieving the PDF metadata.
        string metadata = GdViewer1.PdfGetMetadata();
        if (GdViewer1.GetStat() == GdPictureStatus.OK)
        {
            string metadataFile = filename.Replace(".pdf", "_metadata.xmp");
            System.IO.File.WriteAllText(metadataFile, metadata);
            message += "\nMetadata has been successfully saved. File: " + metadataFile;
        }
        else
            message += "\nMetadata has not been retrieved. Status: " + GdViewer1.GetStat().ToString();
    }
    else
    {
        message += "\nThis file is not a PDF document, its format is: " + GdViewer1.GetDocumentType().ToString();
    }
    MessageBox.Show(message, "GdViewer.PdfGetMetadata");
}
else
    MessageBox.Show("The file can't be loaded. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.PdfGetMetadata");

Reference

GdViewer Class
GdViewer Members
GetLastPath Method
GetDocumentType Method
PdfGetKeywords Method
PdfGetVersion Method
PdfGetCreator Method
PdfGetProducer Method