主题：[求助]设计一段备份的代码

If filesys.directoryexists(args(0)) = False OrElse filesys.directoryexists(args(1)) = False Then Return Nothing
For Each fns As String In filesys.GetFiles(args(0)) 'fileNameSource
   
    Dim fnt As String = args(1) & "\" & filesys.GetName(fns) 'fileNameTarget
   
    If filesys.FileExists(fnt) = False Then
       
        output.show("step1")
       
        filesys.copyfile(fns,fnt)
       
    Else '比较修改时间
       
        Dim fis As new fileinfo(fns) 'fileinfoSource
       
        Dim fist As Date = fis.lastwritetime 'fileinfoSourceTime
       
        Dim fit As new fileinfo(fnt) 'fileinfoTarget
       
        Dim fitt As Date = fit.lastwritetime 'fileinfoTargetTime
       
        If fitt < fist Then
           
            filesys.copyfile(fns,fnt,True)
           
        End If
       
    End If
   
Next

'子文件夹
For Each fns As String In filesys.GetDirectories(args(0)) 'fileNameSource
   
    Dim fnt As String = args(1) & fns.replace(args(0),"")
    If FileSys.DirectoryExists(fnt) = False Then
        FileSys.CreateDirectory(fnt)
    End If
    Functions.Execute("backup", fns,fnt) '递归调用本身
   
Next

Return Nothing