Crystal Reports™ 8.5 Developer's Guide

The Best Tool for Your Needs
We’ve ensured backward compatibility in Crystal Reports 8 to allow you to
leverage applications created in the previous version. However, the Crystal Report
Automation Server no longer exposes all of the events and properties of the Report
Engine in Crystal Reports 8. Because the Report Designer Component is COMbased,
and an evolution of the Crystal Reports Automation Server, you will find it
easy to migrate from the Crystal Reports Automation Server to the RDC.
Report Designer Component (RDC)
The RDC—introduced in June 1998 as a component of Crystal Reports—represents
a major reengineering of the Crystal Report Print Engine. Unlike any of its
predecessors, the RDC is not a wrapper; it exposes all Report Engine objects
directly without any translation. The RDC is based on the same object model as the
Crystal Report Automation Server. Because it is not a wrapper, the RDC is a much
more efficient COM object that supports features such as dual interface, providing
a more efficient way of making calls to the Report Engine.
The primary advantage of using the RDC over other developer tools within Crystal
Reports is its code writing and formatting capabilities in popular development
environments such as Visual Basic. The RDC provides events that enable you to
manipulate the report at runtime. Within these event handlers, you can access text
or field objects to modify the output of a report based on user input. Setting text in
text objects or field objects, or dynamically changing pictures in picture objects, are
added features unique to this interface.
The Best Tool for Your Needs
We recommend that you use the RDC to take advantage of the best functionality
and features available. While we support applications created using other tools
like the OCX and the Crystal Report Print Engine APIs, the RDC offers more power
and is easier to use.
New features of the Crystal Report Print Engine are only available through the
RDC. If you’d like to integrate them into your applications, you must change the
code. Links to resources (technical briefs and tutorials) to help you migrate to the
RDC are located on the Seagate Software Developer Zone web site.
Visit the Seagate Software Developers Zone at
http://www.seagatesoftware.com/products/dev_zone
to find information on the resource that best suits your needs. Chapter 9, “Migrating
to the RDC from the OCX” on page 119 of this guide shows you how to move quickly
to the RDC from the OCX.
TheRDCisthepremiumdevelopmentmethod,anditwillcontinuetobeenhanced
for developers. The latest version of the RDC is included in Crystal Reports 8.5.
14 Crystal Reports Developer’s Guide