[fide]

Hola. Aqui un componente que monitorea la shell y notifica una cantidad de cosas que pueden ser de utilidad...

Aqui les pongo primeramente las explicaciones de la cabecera. Que no entraban en el post:

Código Delphi [-]

//*************************************************************
//*************************************************************
// TSHChangeNotify component by Elliott Shevin  shevine@aol.com
// vers. 3.0, October 2000
//
//   See the README.TXT file for revision history.
//
//*
//*  I owe this component to James Holderness, who described the
//*  use of the undocumented Windows API calls it depends upon,
//*  and Brad Martinez, who coded a similar function in Visual
//*  Basic. I quote here from Brad's expression of gratitude to
//*  James:
//*     Interpretation of the shell's undocumented functions
//*     SHChangeNotifyRegister (ordinal 2) and SHChangeNotifyDeregister
//*     (ordinal 4) would not have been possible without the
//*     assistance of James Holderness. For a complete (and probably
//*     more accurate) overview of shell change notifcations,
//*     please refer to James'  "Shell Notifications" page at
//*     http://www.geocities.com/SiliconValley/4942/
//*
//*  This component will let you know when selected events
//*  occur in the Windows shell, such as files and folders
//*  being renamed, added, or deleted. (Moving an item yields
//*  the same results as renaming it.) For the complete list
//*  of events the component can trap, see Win32 Programmer's
//*  reference description of the SHChangeNotify API call.
//*
//*  Properties:
//*     MessageNo: the Windows message number which will be used to signal
//*                a trapped event. The default is WM_USER (1024); you may
//*                set it to some other value if you're using WM_USER for
//*                any other purpose.
//*     TextCase:  tcAsIs (default), tcLowercase, or tcUppercase, determines
//*                whether and how the Path parameters passed to your event
//*                handlers are case-converted.
//*     HardDriveOnly: when set to True, the component monitors only local
//*                hard drive partitions; when set to False, monitors the
//*                entire file system.
//*
//*  Methods:
//*     Execute:   Begin monitoring the selected shell events.
//*     Stop:      Stop monitoring.
//*
//*  Events:
//*     The component has an event corresponding to each event it can
//*     trap, e.g. OnCreate, OnMediaInsert, etc.
//*     Each event handler is passed either three or four parameters--
//*          Sender=this component.
//*          Flags=the value indentifying the event that triggered the handler,
//*             from the constants in the SHChangeNotify help. This parameter
//*             allows multiple events to share handlers and still distinguish
//*             the reason the handler was triggered.
//*          Path1, Path2: strings which are the paths affected by the shell
//*             event. Whether both are passed depends on whether the second
//*             is needed to describe the event. For example, OnDelete gives
//*             only the name of the file (including path) that was deleted;
//*             but OnRenameFolder gives the original folder name in Path1
//*             and the new name in Path2.
//*             In some cases, such as OnAssocChanged, neither Path parameter
//*             means anything, and in other cases, I guessed, but we always
//*             pass at least one.
//*     Each time an event property is changed, the component is reset to
//*     trap only those events for which handlers are assigned. So assigning
//*     an event handler suffices to indicate your intention to trap the
//*     corresponding shell event.
//*
//*     There is one more event: OnEndSessionQuery, which has the same
//*     parameters as the standard Delphi OnCloseQuery (and can in fact
//*     be your OnCloseQuery handler). This component must shut down its
//*     interception of shell events when system shutdown is begun, lest
//*     the system fail to shut down at the user's request.
//*
//*     Setting CanEndSession (same as CanClose) to FALSE in an
//*     OnEndSessionQuery will stop the process of shutting down
//*     Windows. You would only need this if you need to keep the user
//*     from ending his Windows session while your program is running.
//*
//*   I'd be honored to hear what you think of this component.
//*   You can write me at shevine@aol.com.
//*************************************************************
//*************************************************************
 
{
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Zarko Gajic
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