
Document Type Definitions (DTD) • 121
3.4.2 Types of Attributes
Attributes can be of three types: strings, tokenised, or enumerated. This is shown in Figure 3.26.
Attribute types
Strings Tokenised Enumerated
Figure 3.26 Types of attributes
3.4.2.1 String attributes
String attributes are declared by using the CDATA keyword.
A string attribute can contain any values, except some special characters, such as < > & ‘ or “. We need
to use entity references to define such characters, but more about that later.
3.4.2.2 Tokenised attributes
Tokenised attributes specify certain restrictions that get applied to the attribute values.
Tokenised attributes allow ...