1 / 27

Introduction to XML

Introduction to XML. Module Road Map. Assignment Road Map. Notice we have linked the conduit directly to the presentation layer. This is normally a bad idea!. Introduction to XML. How do we make all of these diverse technologies work together? Extensible Mark-up Language (XML)

chelsa
Download Presentation

Introduction to XML

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Introduction to XML

  2. Module Road Map

  3. Assignment Road Map Notice we have linked the conduit directly to the presentation layer. This is normally a bad idea!

  4. Introduction to XML • How do we make all of these diverse technologies work together? • Extensible Mark-up Language (XML) • Origins in SGML (Standard Generalised Mark-up Language) • Late 1980 early 90s Tim Berners-Lee working in Switzerland devised the first specification for HTML based on SGML

  5. Simple HTML Document • Tags mark-up the content… • Rendered as…

  6. Problems with HTML • The tags were defined as part of the language specification • Different browsers added new features to the language in order to compete • Browser wars

  7. The Marquee Tag

  8. World Wide Web Consortium (W3C) • Devise standards and software related to the World Wide Web • Greater standardisation was applied to HTML leading to XML

  9. Applying Standards • XML HTML, XHTML, Strict, Transitional • We must be good boys and girls • Apple, Opera and Mozilla devised an extension to HTML called Web Forms 2.0 • HTML 5

  10. Two Faces of the Web • HTML 5 – Human Being • XML – Systems • E.g. Netflix - Facebook

  11. XML • A meta-language - data about data • May be used to define other mark-up languages • XML may be used in many other non web related contexts (Office Documents) • Allows us to split data from presentation

  12. Media Centre Master • Tool to manage films saved as DivX files • Creation of scan folders • Communicates with the Internet Movie Database • Web service • Web page versus web document

  13. Viewed in Windows Media Centre

  14. Viewed at IMDB

  15. Tags in XML • XML doesn’t define a large range of tags • If we want to create a new tag in XML we don’t need to wait for a new version of the language • XML allows us define our own mark-up languages • XHTML (eXtensible HyperText Markup Language)

  16. XHTML • Document Type Definition contains a set of rules that define what are allowable tags in an XHTML file

  17. IMDB XML

  18. The XML Declaration • The top line of the file reads as follows... <?xml version="1.0" encoding="utf-8" standalone="yes"?> • XML Version (1.0 or 1.1 – only interested in 1.0) • Encoding – utf-8

  19. Encoding • Everything we see on a computer is internally represented as binary data • How do we translate the following? - 46, 41, 44, 45

  20. The Root Element • A tag that encloses all of the data in the file and must not be empty • XML file for 28 Days Later has a root element of <Title>

  21. Elements • <LocalTitle>28 Days Later</LocalTitle> • Opening tag <LocalTitle> • Closing tag </LocalTitle> • Data 28 Days Later

  22. Attributes and Values • Added to elements to include additional data • (Modified structure to illustrate attributes and values)

  23. Five Rules of XML • 1. Tag names are case sensitive • This is ok... <LocalTitle>28 Days Later</LocalTitle> • This is not... <LocalTitle>28 Days Later</Localtitle> • These are two different tags <localtitle>28 Days Later</localtitle> <LocalTitle>28 Days Later</LocalTitle>

  24. Five Rules of XML • 2. Every opening tag must have a closing tag • This is good... <LocalTitle>28 Days Later</LocalTitle> • This is bad... <LocalTitle>28 Days Later

  25. Five Rules of XML • 3. A nested tag pair cannot overlap another tag

  26. Five Rules of XML • 4. Attribute values must appear within quotes • Good... <FilmDetail Title="28 Days Later" IMDBrating="7.6" ProductionYear="2002"> • Bad... <FilmDetail Title=28 Days Later IMDBrating=7.6 ProductionYear=2002>

  27. Five Rules of XML • 5. Every document must have a root element

More Related