HTML and CSS Reference
As of this writing, HTML5 has not passed the recommendation stage. This
impacts the W3C Markup Validation Service in two ways. First, there is no
W3C validation icon for HTML5. Second, even if your page passes with no
errors, you'll receive a warning that the page was checked with an experimental
feature, the HTML5 Conformance Checker. Because the HTML5 specification
has not been finalized, neither has the validation engine.
TabLe 9-1: Additional W3C Markup Validator Options
Validate Full Document/
Validate HTML Fragment
Available only in the Validate by Direct Input tab . This toggle
allows you to validate a portion of a page or a full page (default) . If
you choose to validate a fragment, you can choose between two
doctypes : HTML 4 .0 1 and XHTML 1 .0. When validating a full page,
you can specify the doctype from a full list (including HTML5) or
allow the validator to detect it automatically.
List Messages Sequentially/
Group Error Messages by
Dictates the error message output format . By default, the validator
details each error as it encounters it in the code, which is read from
top to bottom . Choose Group Error Messages by Type when you'd
prefer to see all similar errors together.
Outputs the entire source code listing of the document validated.
Displays the structured outline of the text headings, <h1> to <h6> .
Validate Error Pages
normally, if the validator cannot find a page entered for validation, it
will display a “file not found error” as returned by the server . When
this option is checked, the validator will attempt to validate the
returned error page.
Displays additional information about the error found, including fuller
explanations and suggested courses of action.
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