Fixed in ASP.NET MVC 4
see http://weblogs.asp.net/jgalloway/archive/2012/02/16/asp-net-4-beta-released.aspx
Conditional attribute rendering
If you have an attribute that might be null, in the past you've needed to do a null check to avoid writing out an empty attribute, like this:
<div @{if (myClass != null) { <text>class="@myClass"</text> } }>Content</div>
Now Razor is able to handle that automatically, so you can just write out the attribute. If it's null, the attribute isn't written:
<div class="@myClass">Content</div>
So if @myClass is null, the output is just this:
<div>Content</div>
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