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Creating or Editing an Unparsed Entity


When working with a DTD, XML Authority includes facilities for creating unparsed entities, which allow documents to reference non-XML information like graphics or other data. XML Authority uses the General Entities tab of the Advanced Pane, shown below in Figure A, to create unparsed entities as well as general entities.

Advanced Pane

Figure A - General Entities tab of the Advanced Pane

Unparsed entities are declared in the bottom pane of the pane, and are identified as unparsed entities by their use of the notation column. Unparsed entities must have a notation identifying their type, and that notation must be declared separately in the notation tab. The notation will be used by the application processing XML documents referencing this entity to determine how to handle the information contained in the entity. The notation provides a shorthand description (typically, things like 'gif' or 'jpeg') that gives the application an idea of what's stored inside the file referenced by the unparsed entity and allows the application to decide whether it wants to use it or not.

An unparsed entity has to have a name, a system reference, and a notation, as shown below in Figure B. It may optionally have a public reference as well.

Creating an Unparsed Entity

Figure B - Creating an unparsed entity (myGraphic)

Unlike general entities, unparsed entities are referenced through attributes of type ENTITY or ENTITIES (which need to be declared in the attribute types pane. Typically, an empty element serves as a container for the attribute, much like the IMG element works in HTML. (Of course, using this approach, the HREF for the element is declared in the entity declaration, not within an HREF attribute of the element itself.)

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