property Edit.hWndPane (Pane as Long) as Long
Gets the window handle of the control's pane.

TypeDescription
Pane as Long A long expression that indicates the index of the pane being queried. The Pane parameter must be greater or equal with 0 and less than 4. The control supports maximum 4 panes. 
Long A long expression that 
The Microsoft Windows operating environment identifies each form and control in an application by assigning it a handle, or hWnd. The hWnd property is used with Windows API calls. Many Windows operating environment functions require the hWnd of the active window as an argument. Use the hWndPane property to retrieve the handle of the pane when control displays splitters. Use the FocusPane property to get the index of the pane that has the focus.  Use the AllowSplitter property to enable splitters in the control.