PdfGetKeywords Method (GdViewer)

In This Topic

Returns the keywords of the currently displayed PDF document, if any is set in the document information dictionary. 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 PdfGetKeywords() As String

public string PdfGetKeywords()

public function PdfGetKeywords(): String;

public function PdfGetKeywords() : String;

public: string* PdfGetKeywords();

public:
String^ PdfGetKeywords();

Return Value

The value of the document's Keywords property as a string. 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 find out the keywords 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 message As String = "The current file is: " + GdViewer1.GetLastPath()
    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.PdfGetKeywords")
Else
    MessageBox.Show("The file can't be loaded. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.PdfGetKeywords")
End If

//We assume that the GdViewer1 control has been properly integrated.
if (GdViewer1.DisplayFromFile("") == GdPictureStatus.OK)
{
    string message = "The current file is: " + GdViewer1.GetLastPath();
    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.PdfGetKeywords");
}
else
    MessageBox.Show("The file can't be loaded. Status: " + GdViewer1.GetStat().ToString(), "GdViewer.PdfGetKeywords");

Reference

GdViewer Class
GdViewer Members
GetLastPath Method
GetDocumentType Method
PdfGetMetadata Method
PdfGetEncryptionScheme Method