Validating html page
HTML is not a regular language and hence cannot be parsed by regular expressions.
Regex queries are not equipped to break down HTML into its meaningful parts. Even enhanced irregular regular expressions as used by Perl are not up to the task of parsing HTML. HTML is a language of sufficient complexity that it cannot be parsed by regular expressions.
If you are using a software product for the first time, you may have to enter the information yourself.
Preferred Method You should always retain a copy of your tax return.
This API allows you to generate and validate XML signatures.
Generally, tax software automatically enters the information for returning customers.
As an alternative you can also try our non-DTD-based validator.
Several introductory and tutorial articles on the Extensible Markup Language (XML) are referenced in the shorter XML Introduction document. "The Extensible Markup Language (XML) is the universal format for structured documents and data on the Web." -- W3C XML Web site, 2000-07-06.
Regex is not a tool that can be used to correctly parse HTML.
Regular expressions are a tool that is insufficiently sophisticated to understand the constructs employed by HTML.