The VirtualPath property returns the virtual path to a local file
name or directory specified by the client as an argument to a standard
FTP command. For example, if the client sends the RETR command to the
server, this property will return the complete virtual path to the file
that the client wants to download. This property will only return a
value for those standard commands that perform some action on a file
or directory, otherwise it will return an empty string.
Setting this property allows you to effectively redirect the client
to use a different file than the one that was actually requested.
If the path is absolute, then it will be used
as-is. If the path is relative, it will be relative to the current
working directory for the active client session. If this property is
set to an empty string, then the server will revert to using the
actual file or directory name specified by the command.
This property should only be set within an OnCommand event
handler, and only for those commands that perform an action on a file
or directory. If the current command does not target a file or
directory, setting this property will cause an exception to be raised
by the control. Exercise caution when using this property to redirect
the server to use a different file than the one requested by the
client; changing the target file may cause the client to behave in
unexpected ways.