Scrapbook 5.2 - Russian translationXHTML: Common Validation Errors
Unescaped Ampersand ("&")
Example:
<a href="foo.cgi?chapter=1§ion=2">...</a>
Possible Validator Report: Unknown entity…
Solution: Always use & in place of &.
Correct Syntax:
<a href="foo.cgi?chapter=1&section=2">...</a>
Incorrect Nesting of Elements
Example:
<strong><em>...</strong></em>
Possible Validator Report: Missing </em> tag
Solution: Elements in XHTML must be closed in the reverse order that they were opened in.
Correct Syntax:
<strong><em>...</em></strong>
Lowercase DOCTYPE
Example:
<!doctype html public "-//w3c//dtd xhtml 1.0 strict//en"
"http://www.w3.org/tr/xhtml1/dtd/xhtml1-strict.dtd" >
Possible Validator Report: Missing DOCTYPE
Solution: The DOCTYPE is case-sensitive so use the correct case.
Correct Syntax::
<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML 1.0 Strict//EN"
"http://www.w3.org/TR/xhtml1/DTD/xhtml1-strict.dtd" >Missing closing " /"
Example:
<img src="image.gif" width="100" height="100" alt="Logo">
Possible Validator Report: Missing closing tag
Solution: So-called "empty elements", such as img,
require a trailing space followed by a "/".
Correct Syntax::
<img src="image.gif" width="100" height="100" alt="Logo" />
Upper case tags
Example:
<STRONG><EM>...</EM></STRONG>
Possible Validator Report: There is no such element…
Solution: Use lower case for all HTML element and attribute names. This difference is necessary because XML is case-sensitive e.g. <em> and <EM> are different tags.
Correct Syntax::
<strong><em>...</em></strong>
Unquoted attribute values
Example:
<td rowspan=3>
Possible Validator Report: Missing " "
Solution: All attribute values must be quoted, even those which appear to be numeric.
Correct Syntax::
<td rowspan="3">
