Add Active And Related Files to Project
The Project | Add Active and Related Files to Project command adds the currently active XML document and all related files to the project. When working on an XML document that is based on a DTD or Schema, this command adds not only the XML document but also all related files (for example, the DTD and all external parsed entities to which the DTD refers) to the current project.
Please note: Files referenced by processing instructions (such as XSLT files) are not considered to be related files.