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Adding HTML5 Validation and Intellisense

Murray Brown
Murray Brown asked

I am trying to create an HTML5 web page in Visual Studio 2010 according to the information at the following link
I followed the instructions below and changed it from  "XHTML 1.0 Transitional" to "HTML5". I have a number
of websites. Will this cause problems with my other projects? Is this a general setting that now governs all the sites I build?

You will definitely want to make sure you have Service Pack 1 installed! By installing Service Pack 1 you get both intellisense (can’t live without that anymore) and validation for HTML5. Don’t forget after you install Service pack 1 to go to Tools | Options | Text Editor | HTML | Validation and set the validation to HTML5 or XHTML5 or the HTML5 validation won’t work.
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Top Expert 2013
In general HTML5 is tolerant of XHTML, however XHTML may not recognize the new features and tags of HTML5.  As long as the doctype specifies XHTML or HTML, there should be no validation issues.  

Going forward XHTML has no future, There are no new versions in the pipeline.  It is a failed experiment that attempted to marry HTML and XML and it ended up with the worst features of both.  HTML5 on the other hand is a living standard that continues to have new feature implemented by browser manufacturers with each new browser release.  Even Microsoft, who have not been very supportive of web standards has committed to implementation of the HTML5 standards.

If you do find incompatibilities, I would recommend that your resolution of them should be to bring the older code up to the new standards rather than trying to find workarounds.


Murray BrownASP.net/VBA/VSTO Developer


Well written! Thanks for the advice. Much appreciated.