Xml Defined

XML – Extensible markup language used to add structure to data.

XML is Extensible – one syntax, many languages

XML separates data

XML is widely accepted public standard

Think of XML as a tree

XML Must Have

• Start and end tags for every element

• It must have one and only one root element

• Empty elements formatted correctly

• Cases can be upper case or lower case

• Elements must nest correctly

• Attribute values must be in quotes

Document Type Definition (DTD) – Specifies structure of the document

Attributes – Additional information stored in elements

XML Element – Then entire components from tag to data

XML Tag – The Starting and Ending tags for an element - is a tag but must have closing to be a complete XML tag

XML Attribute – Property of an element

Elements are:

• EMPTY – Don’t contain any data

• ANY – Contain any permitted content

• Mixed – Contain text and other elements

• Element-Only – Contain only other elements

Processing Instructions – Fire applications to execute code, must have

Extended Backus-Naur Form (EBNF) –Describes syntax for languages EX vowels ::=[aeiou]

< > are called delimiters

- the p is a generic identifier or element name

You can create an element with an entity as:

&chaptertitle;

Entity references allow you to use , &, “, ‘ in attributes and text such as < for , & for &, " for “, and &apos for ‘

CDATA is a large grouping of code similar to being able to process entities.

EX -

CDATA is not allowed in attributes

Each XML document requires XML declaration

Namespaces

EX

4,6,12,14,16,18,20,22

EX

3,11,17,19,23,29,31,37

Document Type Definition DTD

• Defines a set of elements that can appear in a XML document

• Describes what elements can contain in terms of sub-elements and data

• Defines a set of optional or mandatory attributes for each element

• Can be internal located in document or externally located in another file

Symbols in Element Declarations

No...