trying to create a dynamic link in MVC 3
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I'm working on my company's intranet site, On one of the pages I need to include links to .PDF files if they exist. No problem, I got that to work well enough. The problem I'm having is changing the link if the .PDF doesn't exist. Here's what I currently have:
 

    , grid.Column(format: (item) => (File.Exists(item.FileName)==true ? @<a href="@Url.Content(item.FileName)">Art Work</a> : Html.Raw(""))) 



I'm receiving the errors:
Argument 3: cannot convert from 'lambda expression' to 'System.Func<dynamic,object>'	

AND 
The best overloaded method match for 'System.Web.Helpers.WebGrid.Column(string, string, System.Func<dynamic,object>, string, bool)' has some invalid arguments

I've done some due diligence with Google and can't find anything. Can someone tell me where I'm going wrong?
