计算某个目录所占字节数的函数

下面的函数用来计算某个文件目录所占的字节数：

REM 函数返回值为目录所占字节数
Function DirUsedBytes(ByVal dirName As String) As Long
          Dim FileName As String
          Dim FileSize As Currency
          If Right$(dirName, 1) <> "\" Then
               dirName = dirName & "\"
          Endif
          FileSize = 0
          FileName = Dir$(dirName & "*.*")
          Do While FileName <> ""
                 FileSize = FileSize +  FileLen(dirName & FileName)
                FileName = Dir$
          Loop
          DirUsedBytes = FileSize
end function

使用方法：

MsgBox DirUsedBytes("D:\musics")