This example shows how to modify the functionality of an existing PDF Viewer command.
The WinForms PDF Viewer exposes the IPdfViewerCommandFactoryService interface that enables you to substitute the default command with your own custom command.
Create a custom command class (e.g., a CustomNextPageCommand class), inherited from the command that you wish to replace (e.g., PdfNextPageCommand). Override the required method of the command. The main functionality and command specifics is located in the Execute method.
Create a class (e.g., CustomPdfViewerCommandFactoryService) implementing the IPdfViewerCommandFactoryService. Override the CreateCommand method to create an instance of a custom command class if an identifier of a certain command is passed as a parameter. Use the created class to substitute the default PdfViewer's service.