title: How to convert treeView to Json?
body: <p>As the title above how to convert treeView to Json? I check a few links online such as <a href="https://stackoverflow.com/questions/35275335/convert-a-treeview-to-json-using-c-sharp">Convert a Treeview to JSON using C#</a>, but I still don't understand how to convert TreeView to JSON.</p>
  
  <p>Please help, thanks!</p>