title: Determine target framework inside a visual studio code analyzer (Roslyn)
body: <p>I have written a code analyzer (nothing fancy, based on the standard boilerplate code from Microsoft) that helps our teams with the migration of a framework based on classic .Net that has been ported to .net core.  The framework works in net452, net47, netstandard2.0 and .netcoreapp2.2.  Some of the messages emitted by the analyzer only make sense for certain versions of this framework.  Therefore I would like to know that target framework of the code I am currently analyzing.  Can this be done and if so, how ?</p>
  
  <p>tx,
  W</p>