and XML A primer for Web design students

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and XML A primer for Web design
students

• Lee Honeycutt
• English 313

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Today, well cover

• PHP and MySQL for dynamic web pages
• XML Overview
• XML terms and processes
• XML transformations
• XML software
• Impact of XML

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1. What is PHP?

• Originally Personal Home Page, a variant of
  Perl scripting language.
• Open-source language for server-side scripting
  applications.
• Works with variety of relational databases to
  create dynamic web sites on just about any server
  platform.

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Static Web Pages
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Dynamic Web Pages
index.php
Template
XHTML
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Basic PHP Template

• lthtmlgt
• ltbodygt
• lt?php echo "Hello World" ?gt
• lt/bodygt
• lt/htmlgt

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PHP Variables

• lt?php
• txt"Hello World"
• echo txt
• ?gt

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PHP Conditionals

• lt?php
• ddate("D")
• if (d"Fri")
• echo "Have a nice weekend!"
• else
• echo "Have a nice day!"
• ?gt

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PHP Functions

• Similar to JavaScript functions, but more
  powerful. More than 700 unique functions.
• phpinfo( ) function - used for outputting
  information
• phpforms ( ) function - inputting information to
  database

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PHP Form Function

• ltform action"welcome.php method"POST"gt
• Enter your name ltinput type"text" name"name"
  /gt
• Enter your age ltinput type"text" name"age" /gt
• ltinput type"submit" /gt
• lt/formgt

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PHP Example

• English Department reservation system
• Built from open-source program called MRBS
  (Meeting Room Booking System)
• http//reserve.engl.iastate.edu/

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2. XML overview

• XML is a metalanguage, i.e. a language that
  defines the rules and symbols of another
  language.
• XML is not used on the web, but instead used to
  define other markup languages, such as XHTML, the
  replacement of HTML.
• Allows us to define markup languages customized
  to our individual needs instead of relying on
  pre-existing tags.

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Think of XML as.

• An indented outline of a very large document.
• A database table expressed via element tags
  within one big flattened text file.
• A family of technologies that work in tandem to
  express information in a variety of ways.
• The Rosetta Stone of the information age,
  allowing you to move information from one context
  to another through a standardized structure.

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XML Example

• ltaddress typehomegt
• ltnamegt
• ltfirstgtLeelt/firstgt
• ltlastgtHoneycuttlt/lastgt
• lt/namegt
• ltstreetgt404 South Pine Streetlt/streetgt
• ltcitygtEllensburglt/citygt
• ltstategtWAlt/stategtltzip length5gt98926lt/zipgt
• lt/addressgt

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Uses of XML

• Provides a simpler method of structuring large
  data sets compared to earlier tagging systems
  like SGML.
• Publishes information to various media formats
  from a single source.
• Serves as a platform-independent lingua franca
  for sharing hierarchically structured information
  between various programs.
• Embeds links in RSS feeds for news and weblogs.

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3. Key XML Terms Processes

• Elements - similar to HTML lttagsgt, but defined by
  the user instead. They describe, in human
  language, the data they surround.
• Attributes - name and value pairs used to
  distinguish unique instances of an element.
• Entities - shorthand placeholders for information
  used often within a document
• DTDs Schemas - declared dictionaries of
  elements that model a documents content.

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XML Example

• ltaddress typehomegt
• ltnamegt
• ltfirstgtLeelt/firstgt
• ltlastgtHoneycuttlt/lastgt
• lt/namegt
• ltstreetgt404 South Pine Streetlt/streetgt
• ltcitygtEllensburglt/citygt
• ltstategtWAlt/stategtltzip length5gt98926lt/zipgt
• lt/addressgt

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Purpose of DTDs Schemas

• Define the set of allowed tags and attributes in
  the document.
• Describe a documents content model using rules
  by which tags and data are ordered.
• Provide easy model management through references
  to shortcuts and external files.

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4. Transforming XML

• XSL (Extensible Stylesheet Language) - special
  type of XML document that transforms XML data
  into styled format. Similar to HTMLs Cascading
  Stylesheets.
• XSLT (Transformations) - usually used for
  transformation to XHTML.
• XSL-FO (Formatting Objects) - used for page
  formats such as PDF and MS Word.

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XML Transformations
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5. XML Software

• Some applications are moving to XML as their
  foundation. EX OpenOffice.
• Most database programs have an XML export
  feature.
• XML editors and companion components
• Cross Platform - Editix, oXygen, Exchanger
• Windows - XML Spy, XMetal, and Stylus

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6. Impact of XML

• Provides greater flexibility in organizing
  information, but also introduces greater
  complexity.
• Requires greater upfront planning and design of
  information sets and their rhetorical use.
• Separates content from style, which has huge
  rhetorical implications, just as does the use of
  CSS.