Dir（）是否对返回的文件的顺序提供任何保证？ [英] Does Dir() make any guarantee on the order of files returned?

问题描述

我正在清理一些现有的代码

 表格（控制）。选择
 MyDir =单元格（2，1）
 CopySheet =单元格（6，2）
 MyFileName = Dir（MyDir&wp * .xls）
 
'我们知道任何后续调用Dir意味着
'该文件需要添加到列表
而MyFileName& LastFileName 
 MyFileName = Dir 
 Wend 
 
 MyFileName = Dir 
 
虽然MyFileName<> 
细胞（LastRow + 1，1）= MyFileName 
 LastRow = LastRow + 1 
 MyFileName = Dir 
 Wend 
  pre> 
 
 
我的问题与 Dir 如何返回结果以及结果顺序有任何保证。当在上面的循环中使用 Dir 时，代码意味着结果调用 Dir 按名称排序。 
 
 
 
除非 Dir 保证这是一个需要修复的错误。问题是，Dir（）是否对文件的返回顺序进行任何保证？是否隐藏？
 
 
 
解决方案
 
 
 
基于@ Frederic的答案，这是我想出的解决方案。 
 
 
 
使用此快速排序算法连结和功能，返回文件夹中的所有文件 ... 
  Dim allFiles As Variant 
 allFiles = GetFileList（MyDir&wp * .xls）
如果IsArray allFiles）然后
调用QuickSort（allFiles，LBound（allFiles），UBound（allFiles））
 End If 
 
 Dim x As Integer 
 Dim lstFile As String 
x = 1 
 
'仍然需要循环结果才能获得lastFile 
虽然lstFile<> LastFileName 
 lstFile = allFiles（x）
x = x + 1 
 Wend 
 
对于i = x到UBound（allFiles）
 MyFileName = allFiles ）
单元格（LastRow + 1，1）= MyFileName 
 LastRow = LastRow + 1 
 Next i 
  
 
 
解决方案
不能保证 Dir（）将以任何特定的顺序返回文件。  MS Access VBA文档甚至说：
 
 
 提示因为文件名是
，没有特定的顺序，您可以
在数组中存储返回的文件名
，然后将
存储在数组中。
 
 
 
I am trying to clean up some existing code 
Sheets("Control").Select
MyDir = Cells(2, 1)
CopySheet = Cells(6, 2)
MyFileName = Dir(MyDir & "wp*.xls")

' when the loop breaks, we know that any subsequent call to Dir implies
' that the file need to be added to the list
While MyFileName <> LastFileName
    MyFileName = Dir
Wend

MyFileName = Dir

While MyFileName <> ""
    Cells(LastRow + 1, 1) = MyFileName
    LastRow = LastRow + 1
    MyFileName = Dir
Wend
My question relates to how Dir returns results and if there are any guarantees on the order of results. When using Dir in a loop as above, the code implies that the resultant calls to Dir are ordered by name. 

Unless Dir guarantees this, it's a bug which needs to be fixed. The question, does Dir() make any guarantee on the order in which files are returned or is it implicit?

Solution

Based on @Frederic's answer, this is the solution I came up with. 

Using this quicksort algorithm in conjunction and a function that returns all files in a folder ...
Dim allFiles As Variant
allFiles = GetFileList(MyDir & "wp*.xls")
If IsArray(allFiles) Then
    Call QuickSort(allFiles, LBound(allFiles), UBound(allFiles))
End If

Dim x As Integer
Dim lstFile As String
x = 1

' still need to loop through results to get lastFile
While lstFile <> LastFileName 
    lstFile = allFiles(x)
    x = x + 1
Wend

For i = x To UBound(allFiles)
    MyFileName = allFiles(i)
    Cells(LastRow + 1, 1) = MyFileName
    LastRow = LastRow + 1
Next i

解决方案
There's no guarantee that Dir() will return the files in any particular order. The MS Access VBA documentation even says:

  
Tip Because file names are
  retrieved in no particular order, you
  may want to store returned file names
  in an array, and then
  sort the array.


                        
这篇关于Dir（）是否对返回的文件的顺序提供任何保证？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！