HTML Violates Standards and Cannot be Viewed in .NET framework

Generation UPCA in .NET framework HTML Violates Standards and Cannot be Viewed

This chapter looks at some basic HTML issues, especially the newer XHTML standard you should consider for your code I ll show you features in Visual Web Developer that make editing code easier, analyze the structure of your HTML document, and beautify jumbled markup I won t try to teach you HTML tags here because you probably know them already At a minimum, a Web developer s goal should be to keep that pesky HTML close enough to standard usage that a strict browser won t choke on it For my part, I try to keep my HTML clean enough that if some guy snoops at my source code, he won t die laughing I don t want that on my conscience!

XHTML Rulez!

The popular HTML 401 specification is old by Internet standards Anything Internet-related that was officially released at the end of 1999 (and existed long before) is probably today s has-been After all, what browser did you use back in 1999 What search engine was in your Favorites in that browser You get the picture; times change, and HTML is no exception The emerging standard is eXtensible HyperText Markup Language (XHTML) XHTML tightens up the syntax rules so that its HTML meets XML standards

XHTML Rulez!

XML is a cross-platform data format for publishing and exchanging structured documents (For more on applying XML rules to Web pages, refer to sections Making your HTML well-formed and More XHTML requirements, later in this chapter) When you create a Web site from scratch or do an overhaul, you might want to make the move to a higher standard as well Even if you don t see the point of moving to XHTML for today s browsers, consider it a way to future-proof your Web pages Down the road, user-agents (Internet lingo for anything that reads or consumes XHTML) might require XML You don t want to miss out if the Total Informational Computer Knowledge Leaving Earth (TICKLE) project accepts only valid XML documents Once TICKLE is fully funded, it will beam all of Planet Earth s knowledge to distant solar systems Okay, we re kidding about TICKLE (though what the heck, we use it in examples in this chapter) but you never know what else might visit your site or want to parse its data

The World Wide Web Consortium (W3C) is the organization that publishes all sorts of Web-related standards Sadly, it can t enforce any of them Instead of calling its January 26, 2000 specification on XHTML 10 a decree or ukase, the W3C ever so politely invited us to follow it as a recommendation You can read the document at this address:

The dream of a common markup standard for browsers, document readers, TVs, PDAs, and mobile phones didn t grab our attention for several years If the W3C had been really tough with us like threatening to pull the plug on the Internet compliance on the part of browser developers and Webmasters would have started much earlier Even though developers ignored XHTML 10 for years, the W3C wasn t deterred: XHTML 20 is currently in the works

As of this writing, there are four recommended flavors of XHTML XHTML 10 Transitional: This standard supports the tags and attributes in HTML 401, which makes it easier to use when updating existing Web pages If your pages include <font> tags and attributes such as bgcolor, this one s for you This is also the flavor of XHTML used by Visual Web Developer 2005 Express Edition (VWDE) XHTML 10 Strict: This one requires you to use Cascading Style Sheets (CSS) to add color and style to pages That s a very desirable goal for new sites because separating content from presentation lets you update

XHTML Rulez!

the look of a site (for example, the entire color scheme) by swapping in a new CSS file That said, getting that capability may require a lot of rework to get the <font> tags out of all legacy pages XHTML 10 Frameset: The <frameset> tag isn t supported in the Transitional and Strict versions of XHTML 10 The Frameset standard is only for pages that act as frames or containers for other pages XHTML 11: This one takes XHTML 10 Strict and adds support for modules and extensions such as the Scalable Vector Language (SVG) and the Mathematical Markup Language (MathML)