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// ACTIVEX
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Embeds an ActiveX control into a form, providing access to all its functionality.

Control creation:

*** Standard syntax:

   @ nRow, nCol ACTIVEX Name ;
      PROGID cProgID ;
      [ OBJ Obj ; ]
      [ <OF, PARENT> Parent ; ]
      [ WIDTH nWidth ; ]
      [ HEIGHT nHeight ; ]
      [ NOTABSTOP ; ]
      [ DISABLED ; ]
      [ INVISIBLE ; ]
      [ SUBCLASS Subclass ]

*** Alternative syntax:

   DEFINE ACTIVEX Name
      [ COL nCol ]
      [ ROW nRow ]
      PROGID cProgID
      [ OBJECT Obj ]
      [ PARENT Parent ]
      [ WIDTH nWidth ]
      [ HEIGHT nHeight ]
      [ TABSTOP <.T., .F.> ]
      [ <ENABLE, DISABLED> <.T., .F.> ]
      [ <VISIBLE, INVISIBLE> <.T., .F.> ]
      [ SUBCLASS Subclass ]
   END ACTIVEX

*** OOP syntax:

   [ Obj := ] TActiveX():Define( ControlName, [ ParentForm ], [ nCol ], [ nRow ], ;
      [ nWidth ], [ nHeight ], cProgID, [ lNoTabstop ], [ lDisabled ], [ lInvisible ] )

Notes on clauses:

   1. PROGID identifies an ActiveX control. See Active Template Library.
   2. OBJ and OBJECT set a reference to the control into the variable Obj.
      When using OBJECT, the variable must be previously declared.
      When using OBJ, if the variable does not exist, it's assumed PRIVATE.
   3. PARENT declares which window is the parent (owner) of the control.
      Can be ommited only when used inside a DEFINE WINDOW / END WINDOW structure.
   4. ROW and COL define the position of the control inside the parent's client area.
   5. WIDTH and HEIGHT define the dimension of the control.
   6. TABSTOP and NOTABSTOP specify if the control can/can't be focused using TAB key.
      Default is TABSTOP.
   7. DISABLED specifies that the control can't receive mouse clicks and key presses.
      Default is ENABLED.
   8. SUBCLASS indicates that the control must be an instance of the specified class,
      instead of the default TActiveX class.
   9. VISIBLE and INVISIBLE specify if the control must be visible/hidden when
      created. Default is VISIBLE.

Notes on parameters:

   1. nRow, nCol, nWidth and nHeight must be numbers.
   2. Name and Parent must be valid identifiers enclosed or not within quotes.
   3. cProgID must be a string containig a GUID, a ProgID or an URL.
   4. Obj and Subclass must be valid identifiers not enclosed within quotes.
   5. ControlName and ParentForm must be strings containing valid identifiers.
   6. lNoTabstop, lDisabled and lInvisible must be .T. or .F.