+5  A: 

This API is SOAP based. If you want to use it in a .net application you can just add the web reference and code against it. Seems simple enough as it's basically a one-method API...

Assaf Lavie  2009-02-24 20:26:48
I've posted a follow-up question: http://stackoverflow.com/questions/615132/how-might-i-use-the-w3c-markup-validator-api-in-my-net-application
Zack Peterson  2009-03-05 19:22:20
I could use a little help parsing the response: http://stackoverflow.com/questions/616817/how-do-i-extract-data-from-an-xml-file-with-visual-basic
Zack Peterson  2009-03-05 21:58:14

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