Professional Microsoft® SQL Server® 2008 Reporting Services

Appendix A. RDL Object Model

The Report Definition Language (RDL) is a schema-defined XML specification for how a report file should be structured. In order for Reporting Services to interact with the structure of a report, it needs to understand the RDL schema so that it knows which elements represent which pieces of functionality within the report. Although a simple parsing of the XML document, using the XML Document Object Model (DOM) and an XML querying language such as XPath, would technically enable you to extract this information, it would make for very lengthy and cumbersome code to maintain.

Instead, Reporting Services provides a representation of the RDL schema in an object-oriented fashion. What that means is that the RDL schema in Reporting Services was modeled using objects and properties, all available from a public library, which can be used to examine and manipulate the RDL document. This piece of functionality is called the RDL Object Model.

In previous versions of Reporting Services, the object model was not released as a public library and was only available internally to Reporting Services. This meant that a developer had to generate his or her own custom object model based on the RDL schema provided.

You might be asking, "When would I need to use the RDL Object Model?" If you have requirements to generate RDL files on-the-fly or to change any properties of report items, programmatically, this is a great way to do so. It allows for a very flexible platform that ...