OnDirParseStart is a TNotifyEvent property that represents the event handler signalled prior to parsing a textual directory listing into its structured form. 

OnDirParseStart is triggered when attempting to read collection items in an uninitialized DirectoryListing collection. OnDirParseStart is triggered prior to parsing the contents of the ListResult property into collections items using the ListParserClass instance. 

OnDirParseStart allows the application to perform actions need to keep the GUI interface synchronized with the actions of the FTP client; such as clearing the contents of a TListView or TTreeView for the DirectoryListing in the user interface. 

Use OnDirParseEnd to respond to the event notification that occurs when parsing of the directory listing has been completed. 

Use OnRetrievedDir to respond to the event notification that occurs when the textual values in ListResults have been updated.

DirectoryListing 

ListResult 

ListParserClass