ASP.NET 4.5 added support for HTML5 snippets.

HTML5 introduced more than 25 new semantic tags. Visual Studio already had IntelliSense support for these tags, but Visual Studio 2012 makes it faster and easier to write markup by adding some corresponding snippets, like the ones for the audio and video tags.

To invoke the snippet, press Tab twice when the element is selected in IntelliSense:

  <audio controls="controls">
            <source src="file.mp3" type="audio/mp3" />
            <source src="file.ogg" type="audio/ogg" />
  </audio>

This produces a snippet that you can customize.

Automatic renaming of matching tag when you rename an opening or closing tag

If you rename an HTML element (for example, you change a div tag to be a header tag), the corresponding opening or closing tag also changes in real time.

    <heade>
        <audio controls="controls">
            <source src="file.mp3" type="audio/mp3" />
            <source src="file.ogg" type="audio/ogg" />
        </audio>
    </heade>

This helps avoid the error where you forget to change a closing tag or change the wrong one.

Smart indent

When you press Enter while inside an empty HTML element, the editor will put the insertion point in the right place:

If you press Enter in this location, the closing tag is moved down and indented to match the opening tag. The insertion point is also indented: