14. Using XML and XHTML
XML (Extensible Markup Language) is a markup languageit uses tags to label and organize information. Unlike HTML, which uses a predefined set of tags, such as body and form, XML is extensible. You create a set of custom XML tags to contain your data. XML files are plain-text files and don't require any special software to create or interpret them. This makes XML an excellent choice for exchanging data between different hardware platforms or software applications.
Dreamweaver 8 enables you to add an XML file as a data source to your dynamic Web pages. XML files don't contain any formatting information, so in order to display XML data in a browser, you need to attach a style sheeteither CSS (Cascading Style Sheets) or XSLT (Extensible Stylesheet Language Transformations)that contains layout and presentation information. Dreamweaver 8 supports XML, XHTML (Extensible Hypertext Markup Language), XSLT, and XPath (XML Path Language).
XML actually isn't just one languageit's a whole group of languages. XHTML is a reformulation of HTML using XML syntax, and is considered a bridge language between HTML and XML. XSLT is used to add formatting instructions to an XML page and can also be used to generate an HTML page from an XML file. XPath is used with XSLT to specify the exact location of tags and content in an XML file.
In this chapter, you'll learn how to create XHTML documents and convert HTML documents to XHTML. You'll also learn how to create XML files and attach Cascading Style Sheets (CSS). Finally, you'll learn how to convert an HTML page to an XSLT page, attach an XSLT style sheet to an XML file, create an XSLT fragment and add it to a dynamic page, and use Dreamweaver's XPath Expression Builder.
We use PHP in our dynamic page, but ASP, ASP.NET, and ColdFusion can also be used with XSLT in Dreamweaver. Dreamweaver doesn't include support for using JSP and XSLT.