delphi7系统文件备份系统

unitUnit1;interfaceusesWindows,Messages,SysUtils,Classes,Graphics,Controls,Forms,Dialogs,StdCtrls,FileCtrl;typeTForm1=class(TForm)DriveComboBox1:TDriveComboBox;FileListBox1:TFileListBox;DirectoryListBox1:TDirectoryListBox;Button1:TButton;Button2:TButton;ListBox1:TListBox;