Mark Richman

I recently upgraded a website to Visual Studio 2008 from Visual Studio 2005 so I could make use of LINQ to SQL. Upon adding my table to a new .dbml file and rebuilding, I was met with this nasty compiler error:

LINQ to SQL compiler error CS1519: Invalid token ‘void’ in class, struct, or interface member declaration

After a few minutes of cursing Microsoft, I figured it out…looks like the compiler version wasn’t updated in the solution
file…the C# 2.0 compiler was still being used and choked on the
partial methods. I went into project properties, downgraded from
framework 3.5 to 2.0, clicked ok, then went back and set it to 3.5 and
clicked ok. After re-adding the reference to System.Data.Linq, the
compile succeeded.

To me, this is a bug in Visual Studio
2008…the scenario where you “upgrade” a Visual Studio 2005 website to
2008 for use with LINQ seems like a common thing, no?

Dave Yancey confirms this behavior for XMLSerializer bugs as well…thanks Dave!

Update (May 23, 2008): I was told the following would also be helpful, though I have not tested it yet:

<system.codedom>
<compilers>
<compiler language="c#;cs;csharp" extension=".cs" warningLevel="4"
  type="Microsoft.CSharp.CSharpCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<providerOption name="CompilerVersion" value="v3.5"/>
<providerOption name="WarnAsError" value="false"/>
</compiler>
<compiler language="vb;vbs;visualbasic;vbscript" extension=".vb" warningLevel="4"
  type="Microsoft.VisualBasic.VBCodeProvider, System, Version=2.0.0.0, Culture=neutral, PublicKeyToken=b77a5c561934e089">
<providerOption name="CompilerVersion" value="v3.5"/>
<providerOption name="OptionInfer" value="true"/>
<providerOption name="WarnAsError" value="false"/>
</compiler>
</compilers>
</system.codedom>