Click the Preview button on the toolbar to preview a report currently opened in the Web Report Designer. The preview displays a report document - a report populated with data and divided into pages.
The Document Preview is full-featured Document Viewer component integrated into the Report Designer. You can preview, print, export and email a report. The Document Viewer API allows you to customize the preview.
The PreviewReportCustomizationService allows you to change the report settings before the Report Designer generates a report document in the Preview tab. You can implement and register the WebDocumentViewerOperationLogger class descendant to execute custom code when a document is generated, exported, or printed.