title: Get all Included className in Solution
body: <p>is there a way i can get all <em>included class</em> in solution ?
  atleast allClassNames e.g <code>classname.cs</code></p>
  
  <p>but the thing was create the code for finding includedClass <code>in other solution</code> . 
  Means not the solution where I'm doing code but the other solution .</p>
  
  <p>Here's what ive researched so far:</p>
  
  <p><a href="https://stackoverflow.com/questions/707107/library-for-parsing-visual-studio-solution-files">Parsing Visual Studio Solution files</a></p>
  
  <p>but im still confuse on how to get it via path (of .sln)? or how can i implement it .
  thanks in advance!</p>