title: Transform an ItemGroup into a Delimited String
body: <p>My question is almost identical to <a href="https://stackoverflow.com/questions/3498374/create-an-itemgroup-of-strings-in-msbuild">Create an ItemGroup of strings in MSBuild</a> however the solution offered there still seems to carry over the existing delimiter. Here's a simplified snippet of what I'm attempting to do:</p>
  
  <pre><code>&lt;Target Name="Testing"&gt;
    &lt;ItemGroup&gt;
      &lt;Files Include="$(RootDirectory)\*.*"/&gt;
    &lt;/ItemGroup&gt;
  
    &lt;Message Text="@(Files-&gt;'%(Filename)%(Extension) ')"/&gt;
  &lt;/Target&gt;
  </code></pre>
  
  <p>My desired output is something that looks like this:</p>
  
  <pre><code>file1.cs file2.cs file3.cs
  </code></pre>
  
  <p>However the snippet above produces the following output</p>
  
  <pre><code>file1.cs ;file2.cs ;file3.cs
  </code></pre>
  
  <p>What have I done wrong?</p>