title: Get list of open windows form instance that are excuted from different assembly
body: <p>I have a 'loader app' that loads a menu and when user clicks the menu image button a list view opens based on the text </p>
  
  <pre><code>(if text = employee)  
  (Go to class A) 
  (Go to class B) 
      ...
      ...
      (Show List View Window) 
  </code></pre>
  
  <p>if he clicks again on the same button it opens again, I would like to prevent this.
  i.e but this for a WPF application</p>