Set custom XMP metadata properties
This sample shows how to change custom (application-defined) metadata properties of a PDF document. These properties are displayed in the Additional Metadata view and on the Custom tab of Document Properties dialog of Adobe Acrobat Professional.
Docotic.Pdf can be used to read and set strings, arrays of different types and structures as custom properties. To access custom metadata properties of a PDF document, use PdfDocument.Metadata.Custom property.