This chapter lists out various tips and tricks which you should be aware of while writing an XHTML document. These tips and tricks can help you create effective documents.
Here are some basic guidelines for designing XHTML documents −
When you think of satisfying what your audience wants, you need to design effective and catchy documents to serve the purpose. Your document should be easy for finding required information and giving a familiar environment.
For example, Academicians or medical practitioners are comfortable with journal-like document with long sentences, complex diagrams, specific terminologies, etc., whereas the document accessed by school-going children must be simple and informative.
Reuse your previously created successful documents instead of starting from scratch each time you bag a new project.
Here are some tips regarding elements inside the XHTML document −
An XML declaration is not required in all XHTML documents but XHTML document authors are strongly encouraged to use XML declarations in all their documents. Such a declaration is required when the character encoding of the document is other than the default UTF-8 or UTF-16.
They include a space before the trailing / and > of empty elements. For example, <br />, <hr />, and <img src="/html/xhtml.gif" alt="xhtml" />.
Use external style sheets if your style sheet uses “<”, “&”, “]]>”, or “—”.
Use external scripts if your script uses “<”, “&”, or “]]>”, or “—”.
Avoid line breaks and multiple whitespace characters within attribute values. These are handled inconsistently by different browsers.
Do not include more than one isindex element in the document head. The isindex element is deprecated in favor of the input element.
Use both the lang and xml:lang attributes while specifying the language of an element. The value of the xml:lang attribute takes precedence.
XHTML 1.0 has deprecated the name attributes of a, applet, form, frame, iframe, img, and map elements. They will be removed from XHTML in subsequent versions. Therefore, start using id element for element identification.
The ampersand character ("&") should be presented as an entity reference &.
<!-- This is invalid in XHTML --> http://my.site.dom/cgi-bin/myscript.pl?class=guest&name=user. <!-- Correct XHTML way of writing this is as follows --> http://my.site.dom/cgi-bin/myscript.pl?class=guest&name=user
Some characters that are legal in HTML documents are illegal in XML document. For example, in HTML, the form-feed character (U+000C) is treated as white space, in XHTML, due to XML's definition of characters, it is illegal.
The named character reference ' (the apostrophe, U+0027) was introduced in XML 1.0 but does not appear in HTML. Web developers should therefore use ' instead of ' to work as expected in HTML 4 Web Browsers.