Report viewers

Crystal Enterprise includes report viewers that support different platforms and different browsers in the client tier, and which have different report viewing functionality. (For more information on the specific functionality or platform support provided by each report viewer, see the Crystal Enterprise User's Guide or the Crystal Reports Developer's Guide.)

All of the viewers fall into two categories: client-side viewers, and zero client viewers. Client-side viewers are downloaded and installed in the users' web browser while the code to support zero client viewers resides in the application tier.

client-side viewers	zero client viewers
Active X viewer	DHTML viewer
Java viewer	Advanced DHTML viewer

All report viewers help process requests for reports, and present report pages that appear in the user's browser.

Zero client viewers reside on the application server. When a user requests a report, the application server processes the request, and then retrieves the report pages in .epf format from the Crystal Enterprise framework. The SDK creates a viewer object on the application server which processes the .epf and creates DHTML pages that represent both the viewer controls and the report itself. The viewer object then sends these pages through the web server to the user's web browser.

Client-side viewers are downloaded and installed in the user's browser. When a user requests a report, the application server processes the request, and retrieves the report pages in .epf format from the Crystal Enterprise framework. The application server then passes the .epf file to the client-side viewer, which processes the .epf files and displays them directly in the browser.

If they haven't already done so, users are prompted to download and install the appropriate viewer software before the report is displayed in the browser. The Active X viewer is downloaded the first time a user requests a report, and then remains installed on the user's machine. You will be prompted to reinstall the ActiveX viewer only when a new version becomes available on the server.