Introduction to the Crystal Report Viewers

The Crystal Report viewers that ship with Report Application Server break into four different categories to suit the need of a variety of applications: the Page viewer, Part viewer, Interactive viewer, and Grid viewer. Although all four viewers offer unique capabilities, they share a common API and set of basic features. Each viewer allows the developer to indicate which report to display, supply database logon credentials, apply report parameters, and export the report. All four viewers are exposed as server-side controls and as a result, output dynamic HTML that is rendered in any Web browser. No special software is required on the clients machines to view reports using any of the viewers.

Listed below is a short description about each report viewer:

• Page viewer: The standard report viewer component. It displays reports in a paginated fashion. A toolbar along the top allows access functions like page navigation, printing, exporting, zooming, and text searching.
• Part viewer: A report viewer component that renders just individual elements of a report. This is useful for portal-style applications where only a small portion of the screen is reserved for report viewing.
• Interactive viewer: Looks and acts identical to the Page viewer but exposes an extra toolbar button that provides an additional user interface for doing data-level searching within the report.
• Grid viewer: A viewer component that just displays the data from the report in a grid without any layout or formatting applied.

The means with which all of these viewers interact with the reports themselves is a mechanism called the report source. The following section describes the report source in detail.