Simple MSBuild task to find items in ItemGroup

FindInEnumeration.xml

<UsingTask TaskName="FindInEnumeration" TaskFactory="CodeTaskFactory"
  		   AssemblyFile="$(MSBuildToolsPath)\Microsoft.Build.Tasks.v4.0.dll">
	<ParameterGroup>
		<SourceFiles ParameterType="Microsoft.Build.Framework.ITaskItem[]" Required="true" />
		<Files ParameterType="Microsoft.Build.Framework.ITaskItem[]" Required="true" />
		<Result ParameterType="Microsoft.Build.Framework.ITaskItem[]" Output="true" />
	</ParameterGroup>
	<Task>
		<Reference Include="System" />
		<Reference Include="System.Core" />
		<Reference Include="System.Xml" />
		<Reference Include="System.Xml.Linq" />
		<Reference Include="Microsoft.CSharp" />
		<Using Namespace="System" />
		<Using Namespace="System.Reflection" />
		<Using Namespace="System.IO" />
		<Using Namespace="System.Linq" />
		<Using Namespace="System.Xml.Linq" />
		<Using Namespace="System.Net" />
		<Using Namespace="Microsoft.Build.Framework" />
		<Using Namespace="Microsoft.Build.Utilities" /> 

		<Code Type="Fragment" Language="cs">
			<![CDATA[
				try
				{
					var filesToFind = Files.Select(item => item.GetMetadata("FullPath")).ToArray();

					Result = SourceFiles
						.Where(file => filesToFind.Contains(file.ItemSpec))
						.ToArray();
						
					return true;
				}
				catch (Exception ex)
				{
					Log.LogErrorFromException(ex);
					return false;
				}
			]]>
	    </Code>
	</Task>
</UsingTask>