I always edit CSS in Dreamweaver or Notepad (My friends always scream when they see me using Notepad to write CSS or HTML). Recently, I’m writing a web app to be deployed on Azure. So, I have the chance to edit CSS in Visual Studio 2010.
Visual Studio also provides us CSS validation. However, soon I found that VS kept warning me for having unknown CSS property names. I guessed that was due to the fact that it’s using an older CSS version for validation. Yappari, the “CSS Version for Validation” dropdown list showed that it’s currently using CSS 2.1. Thus, VS didn’t know the new property names introduced in CSS 3.
To solve that, I followed the steps suggested by Garry in StackOverflow. What I need to do is basically just downloading and then installing the “CSS 3 Intellisense Schema” (Free!) from VS extensions gallery: http://visualstudiogallery.msdn.microsoft.com/7211bcac-091b-4a32-be2d-e797be0db210.
In the discussion forum, there is a user, Nibblersrevenge, saying that if the CSS 3 validation entry was enabled even after the installation, we should copy the file “css30.xml” from the folder “C:\Program Files\Microsoft Visual Studio 10.0\Common7\Packages\1033\schemas\CSS” to the folder “C:\Program Files\Microsoft Visual Studio 10.0\Common7\Packages\1031\schemas\CSS”. Luckily, I didn’t encounter this problem.
After the installation is done, I can see the newly added CSS 3.0 option being added to the CSS validation dropdown. The warnings previously generated by VS are all gone after I change the CSS validation to CSS 3.0. Yay.
EDIT (27 April 2013): As iamprabhanshu pointed out in the comments section, if the CSS 3.0 option is still not available in the dropdown list after the installation, please close the Visual Studio and re-open it.