PRB: TreeView Control HitTest Method Returns Empty String

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Comctl32.ocx, version 1.0.2908, returns NULL in the TreeView HitTest method when there is no Node at the specified coordinates. Version 5.00.3714 returns an empty string. In Visual Basic, both versions of the OCX return nothing (NULL). Visual FoxPro appears to be handling the return value differently. The behavior occurs in both Visual FoxPro 5.0 and Visual FoxPro 5.0a. The newest version of the OCX ships with Visual FoxPro 5.0a. The following code illustrates the behavior:

   =SYS(2333,1)                && to make sure VTABLE binding is on
   *=SYS(2333,0)               && as a test, unremark this and rerun code
   frmOLEForm=CREATEOBJECT('form')
   frmOLEForm.Show
   =MessageBox('In the next dialog box, choose the "Insert Control" '+ ;
      'button and then the "Microsoft TreeView Control" from the list.',0)
   frmOLEForm.AddObject('OLETree1','olecontrol')
   frmOLEForm.OLETree1.Visible = .T.
   =SYS(2333,1)                && this is optional

   ACTIVATE SCREEN

   xHitTest=frmOLEForm.OLETree1.HitTest(1,1)
   ? TYPE("xHitTest")
   ? IIF(ISBLANK(xHitTest), 'Empty', xHitTest)
   * The following is the workaround if VTABLE binding is not disabled
   ? IIF(ISBLANK(xHitTest), .NULL., xHitTest)
				

TYPE("xHitTest") should return "O" for object, because, according to the Help file, the HitTest method returns an object reference. In the newest version of the OCX and with ActiveX Dual Interface support enabled, xHitTest will return a Character type ("C") with a value of blank or "empty."