Q185476: HOWTO: Search Directories to Find or List Files
Article: Q185476
Product(s): Microsoft Visual Basic for Windows
Version(s): 4.0,5.0,6.0
Operating System(s):
Keyword(s): kbAPI KbVBA kbVBp kbVBp500 kbVBp600 kbOSWin32s kbDSupport
Last Modified: 20-JAN-2001
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The information in this article applies to:
- Microsoft Visual Basic Learning Edition for Windows, versions 5.0, 6.0
- Microsoft Visual Basic Professional Edition for Windows, versions 5.0, 6.0
- Microsoft Visual Basic Enterprise Edition for Windows, versions 5.0, 6.0
- Microsoft Visual Basic Standard Edition, 32-bit, for Windows, version 4.0
- Microsoft Visual Basic Professional Edition, 32-bit, for Windows, version 4.0
- Microsoft Visual Basic Enterprise Edition, 32-bit, for Windows, version 4.0
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SUMMARY
=======
When looking for files, it is often necessary to search through subdirectories.
This article demonstrates two methods for recursively searching directories and
retrieving file information.
MORE INFORMATION
================
While Visual Basic provides methods for retrieving information about files and
directories, you may also use Windows API functions for these tasks. Using the
API is not faster than the built in methods, but the two methods work a little
differently. So, this article demonstrates both techniques for retrieving this
information. If you test both methods, try using the same starting path and
search string. You should get similar results.
Visual Basic for Applications (VBA) includes an Application.FileSearch object
that can be used to find and list files. While not directly available in Visual
Basic, you can use it from a Microsoft Office 97 product. More information and
examples can be found in the Online Help, and by searching the Microsoft
Knowledge Base for "FileSearch."
Please note that the following examples do not include full error trapping, but
Method 2 does catch a special case where the VB GetAttr() function fails on
Pagefile.sys, which is the Windows NT virtual memory paging file. Also,
depending on the search string, the API version lists and counts directory names
by default, where the VB version does not. Please note that the following
examples do not include full error trapping, but Method 2 does catch a special
case where the VB GetAttr() function fails on Pagefile.sys, which is the Windows
NT virtual memory paging file. The only difference in results between these two
methods is that the VB code does not return the file create dates.
Method 1: Using the Windows API
-------------------------------
1. Start a new Standard EXE project in Visual Basic. Form1 is created by
default.
2. Add a CommandButton named Command1, four TextBoxes named Text1, Text2, Text3
and Text4 and a ListBox to Form1.
3. Add a Module from the Projects menu and insert the following:
Declare Function FindFirstFile Lib "kernel32" Alias _
"FindFirstFileA" (ByVal lpFileName As String, lpFindFileData _
As WIN32_FIND_DATA) As Long
Declare Function FindNextFile Lib "kernel32" Alias "FindNextFileA" _
(ByVal hFindFile As Long, lpFindFileData As WIN32_FIND_DATA) As Long
Declare Function GetFileAttributes Lib "kernel32" Alias _
"GetFileAttributesA" (ByVal lpFileName As String) As Long
Declare Function FindClose Lib "kernel32" (ByVal hFindFile As Long) _
As Long
Declare Function FileTimeToLocalFileTime Lib "kernel32" _
(lpFileTime As FILETIME, lpLocalFileTime As FILETIME) As Long
Declare Function FileTimeToSystemTime Lib "kernel32" _
(lpFileTime As FILETIME, lpSystemTime As SYSTEMTIME) As Long
Public Const MAX_PATH = 260
Public Const MAXDWORD = &HFFFF
Public Const INVALID_HANDLE_VALUE = -1
Public Const FILE_ATTRIBUTE_ARCHIVE = &H20
Public Const FILE_ATTRIBUTE_DIRECTORY = &H10
Public Const FILE_ATTRIBUTE_HIDDEN = &H2
Public Const FILE_ATTRIBUTE_NORMAL = &H80
Public Const FILE_ATTRIBUTE_READONLY = &H1
Public Const FILE_ATTRIBUTE_SYSTEM = &H4
Public Const FILE_ATTRIBUTE_TEMPORARY = &H100
Type FILETIME
dwLowDateTime As Long
dwHighDateTime As Long
End Type
Type WIN32_FIND_DATA
dwFileAttributes As Long
ftCreationTime As FILETIME
ftLastAccessTime As FILETIME
ftLastWriteTime As FILETIME
nFileSizeHigh As Long
nFileSizeLow As Long
dwReserved0 As Long
dwReserved1 As Long
cFileName As String * MAX_PATH
cAlternate As String * 14
End Type
Type SYSTEMTIME
wYear As Integer
wMonth As Integer
wDayOfWeek As Integer
wDay As Integer
wHour As Integer
wMinute As Integer
wSecond As Integer
wMilliseconds As Integer
End Type
Public Function StripNulls(OriginalStr As String) As String
If (InStr(OriginalStr, Chr(0)) > 0) Then
OriginalStr = Left(OriginalStr, _
InStr(OriginalStr, Chr(0)) - 1)
End If
StripNulls = OriginalStr
End Function
4. Copy the following code into Form1's module:
Option Explicit
Function FindFilesAPI(path As String, SearchStr As String, _
FileCount As Integer, DirCount As Integer)
Dim FileName As String ' Walking filename variable...
Dim DirName As String ' SubDirectory Name
Dim dirNames() As String ' Buffer for directory name entries
Dim nDir As Integer ' Number of directories in this path
Dim i As Integer ' For-loop counter...
Dim hSearch As Long ' Search Handle
Dim WFD As WIN32_FIND_DATA
Dim Cont As Integer
Dim FT As FILETIME
Dim ST As SYSTEMTIME
Dim DateCStr As String, DateMStr As String
If Right(path, 1) <> "\" Then path = path & "\"
' Search for subdirectories.
nDir = 0
ReDim dirNames(nDir)
Cont = True
hSearch = FindFirstFile(path & "*", WFD)
If hSearch <> INVALID_HANDLE_VALUE Then
Do While Cont
DirName = StripNulls(WFD.cFileName)
' Ignore the current and encompassing directories.
If (DirName <> ".") And (DirName <> "..") Then
' Check for directory with bitwise comparison.
If GetFileAttributes(path & DirName) And _
FILE_ATTRIBUTE_DIRECTORY Then
dirNames(nDir) = DirName
DirCount = DirCount + 1
nDir = nDir + 1
ReDim Preserve dirNames(nDir)
' Uncomment the next line to list directories
'List1.AddItem path & FileName
End If
End If
Cont = FindNextFile(hSearch, WFD) ' Get next subdirectory.
Loop
Cont = FindClose(hSearch)
End If
' Walk through this directory and sum file sizes.
hSearch = FindFirstFile(path & SearchStr, WFD)
Cont = True
If hSearch <> INVALID_HANDLE_VALUE Then
While Cont
FileName = StripNulls(WFD.cFileName)
If (FileName <> ".") And (FileName <> "..") And _
((GetFileAttributes(path & FileName) And _
FILE_ATTRIBUTE_DIRECTORY) <> FILE_ATTRIBUTE_DIRECTORY) Then
FindFilesAPI = FindFilesAPI + (WFD.nFileSizeHigh * _
MAXDWORD) + WFD.nFileSizeLow
FileCount = FileCount + 1
' To list files w/o dates, uncomment the next line
' and remove or Comment the lines down to End If
'List1.AddItem path & FileName
' Include Creation date...
FileTimeToLocalFileTime WFD.ftCreationTime, FT
FileTimeToSystemTime FT, ST
DateCStr = ST.wMonth & "/" & ST.wDay & "/" & ST.wYear & _
" " & ST.wHour & ":" & ST.wMinute & ":" & ST.wSecond
' and Last Modified Date
FileTimeToLocalFileTime WFD.ftLastWriteTime, FT
FileTimeToSystemTime FT, ST
DateMStr = ST.wMonth & "/" & ST.wDay & "/" & ST.wYear & _
" " & ST.wHour & ":" & ST.wMinute & ":" & ST.wSecond
List1.AddItem path & FileName & vbTab & _
Format(DateCStr, "mm/dd/yyyy hh:nn:ss") _
& vbTab & Format(DateMStr, "mm/dd/yyyy hh:nn:ss")
End If
Cont = FindNextFile(hSearch, WFD) ' Get next file
Wend
Cont = FindClose(hSearch)
End If
' If there are sub-directories...
If nDir > 0 Then
' Recursively walk into them...
For i = 0 To nDir - 1
FindFilesAPI = FindFilesAPI + FindFilesAPI(path & dirNames(i) _
& "\", SearchStr, FileCount, DirCount)
Next i
End If
End Function
Private Sub Command1_Click()
Dim SearchPath As String, FindStr As String
Dim FileSize As Long
Dim NumFiles As Integer, NumDirs As Integer
Screen.MousePointer = vbHourglass
List1.Clear
SearchPath = Text1.Text
FindStr = Text2.Text
FileSize = FindFilesAPI(SearchPath, FindStr, NumFiles, NumDirs)
Text3.Text = NumFiles & " Files found in " & NumDirs + 1 & _
" Directories"
Text4.Text = "Size of files found under " & SearchPath & " = " & _
Format(FileSize, "#,###,###,##0") & " Bytes"
Screen.MousePointer = vbDefault
End Sub
5. Run the Project. Enter a starting path into Text1, a search string in Text2
(like *.* or *.txt) and then click Command1.
You will see a list of the files found display in the ListBox with the create
date and the last modified date, the actual number of files found displays in
Text3, and the total size of the files found under the starting directory
appears in Text4.
Method 2: Using Built-In Visual Basic Functions
-----------------------------------------------
These instructions build on the sample described prior, but can also be used in a
new Project.
1. Open the Project by using the steps described in Method1
2. Add another CommandButton named Command2, two more TextBoxes named Text5 and
Text6 and another ListBox, List2, to Form1.
3. Copy the following code into Form1's module:
Function FindFiles(path As String, SearchStr As String, _
FileCount As Integer, DirCount As Integer)
Dim FileName As String ' Walking filename variable.
Dim DirName As String ' SubDirectory Name.
Dim dirNames() As String ' Buffer for directory name entries.
Dim nDir As Integer ' Number of directories in this path.
Dim i As Integer ' For-loop counter.
On Error GoTo sysFileERR
If Right(path, 1) <> "\" Then path = path & "\"
' Search for subdirectories.
nDir = 0
ReDim dirNames(nDir)
DirName = Dir(path, vbDirectory Or vbHidden Or vbArchive Or vbReadOnly _
Or vbSystem) ' Even if hidden, and so on.
Do While Len(DirName) > 0
' Ignore the current and encompassing directories.
If (DirName <> ".") And (DirName <> "..") Then
' Check for directory with bitwise comparison.
If GetAttr(path & DirName) And vbDirectory Then
dirNames(nDir) = DirName
DirCount = DirCount + 1
nDir = nDir + 1
ReDim Preserve dirNames(nDir)
'List2.AddItem path & DirName ' Uncomment to list
End If ' directories.
sysFileERRCont:
End If
DirName = Dir() ' Get next subdirectory.
Loop
' Search through this directory and sum file sizes.
FileName = Dir(path & SearchStr, vbNormal Or vbHidden Or vbSystem _
Or vbReadOnly Or vbArchive)
While Len(FileName) <> 0
FindFiles = FindFiles + FileLen(path & FileName)
FileCount = FileCount + 1
' Load List box
List2.AddItem path & FileName & vbTab & _
FileDateTime(path & FileName) ' Include Modified Date
FileName = Dir() ' Get next file.
Wend
' If there are sub-directories..
If nDir > 0 Then
' Recursively walk into them
For i = 0 To nDir - 1
FindFiles = FindFiles + FindFiles(path & dirNames(i) & "\", _
SearchStr, FileCount, DirCount)
Next i
End If
AbortFunction:
Exit Function
sysFileERR:
If Right(DirName, 4) = ".sys" Then
Resume sysFileERRCont ' Known issue with pagefile.sys
Else
MsgBox "Error: " & Err.Number & " - " & Err.Description, , _
"Unexpected Error"
Resume AbortFunction
End If
End Function
Private Sub Command2_Click()
Dim SearchPath As String, FindStr As String
Dim FileSize As Long
Dim NumFiles As Integer, NumDirs As Integer
Screen.MousePointer = vbHourglass
List2.Clear
SearchPath = Text1.Text
FindStr = Text2.Text
FileSize = FindFiles(SearchPath, FindStr, NumFiles, NumDirs)
Text5.Text = NumFiles & " Files found in " & NumDirs + 1 & _
" Directories"
Text6.Text = "Size of files found under " & SearchPath & " = " & _
Format(FileSize, "#,###,###,##0") & " Bytes"
Screen.MousePointer = vbDefault
End Sub
Private Sub Form_Load()
Command1.Caption = "Use API code"
Command2.Caption = "Use VB code"
' start with some reasonable defaults
Text1.Text = "C:\My Documents\"
Text2.Text = "*.*"
End Sub
4. Run the Project. Enter a starting path into Text1, a search string in Text2
(like *.* or Myfile?.txt, and so forth) and then click Command2.
You see a list of the files found appear in List2 with the last modified date,
the number of files found in Text5, and the total size of the files found under
the starting directory in Text6. By combining these two methods on one form you
can verify that both methods return matching information.
Method 3: Use the FileSystem Object with Visual Basic
-----------------------------------------------------
For information about using the FileSystemObject with Visual Basic to find or
list files, please see the following article in the Microsoft Knowledge Base:
Q185601 HOWTO: Recursively Search Directories Using FileSystemObject
Additional query words:
======================================================================
Keywords : kbAPI KbVBA kbVBp kbVBp500 kbVBp600 kbOSWin32s kbDSupport
Technology : kbVBSearch kbAudDeveloper kbZNotKeyword6 kbZNotKeyword2 kbVB500Search kbVB600Search kbVBA500 kbVBA600 kbVB500 kbVB600 kbVB400Search kbVB400
Version : :4.0,5.0,6.0
Issue type : kbhowto
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