DTD tutorial

DTD is described in W3C XML 1.0 standard. In this tutorial basic DTD features are demonstrated on many examples.

Standard excerpt:
The XML document type declaration contains or points to markup declarations that provide a grammar for a class of documents. This grammar is known as a document type definition, or DTD. The document type declaration can point to an external subset (a special kind of external entity) containing markup declarations, or can contain the markup declarations directly in an internal subset, or can do both. The DTD for a document consists of both subsets taken together.

Introduction

• Root element
• Elements in given order ( , )
• Zero or more children ( * )
• One or more children ( + )
• Zero or one child ( ? )
• Zero or one child ( ? )
• Children from a selection ( | )
• Combibation of text and elements
• Attributes
• Attributes: CDATA, NMTOKEN, NMTOKENS
• Attributes: ID
• Attributes: IDREF, IDREFS
• Attribute's values from selection
• Default attribute value
• Empty elements