Visual Studio 2010 environment variable

I've set an environment variable named %SDK% in windows. Can I use it somehow in .csproj file?

Something like:

<ItemGroup>
  <Reference Include="SomeDll">
    <HintPath>%SDK%\SomeDll.dll</HintPath>
  </Reference>
</ItemGroup&g开发者_运维问答t;

I've tried %SDK% and $(SDK) and it does not work. Any ideas?

---

OMG, I had wrong path set in that variable. It works with:

<ItemGroup>
  <Reference Include="SomeDll">
    <HintPath>$(SDK)\SomeDll.dll</HintPath>
  </Reference>
</ItemGroup>