HOW TO: Recursively Search Directories by Using FileSystemObject (185601)

SUMMARY

This step-by-step article demonstrates how to use the FileSystemObject class to recursively search directories and to find specific files.

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Information About the FileSystemObject Class

The FileSystemObject class is located in the Microsoft Scripting Runtime (Scrrun.dll). To obtain the Scrrun.dll file, install any of the following packages:

• Microsoft Windows Script Host
• Microsoft Windows NT Option Pack
• Microsoft Internet Information Server 3.0
• Scripting 3.1 upgrade
• Microsoft Visual Studio 98
• Microsoft Visual Basic 6.0

The FileSystemObject class provides better performance than if you use Visual Basic intrinsic functions such as Dir and GetAttr. Additionally, FileSystemObject is much simpler to implement that the Visual Basic intrinsic functions.

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Build the Sample

1. Create a new Standard EXE project in Visual Basic. By default, Form1 is created.
2. On the Project menu, click References, and then add a reference to the Microsoft Scripting Runtime. If this option is not listed, locate the Scrrun.dll file on your system. If you have to, install one of the tools that is listed in the Information About the FileSystemObject Class section.
3. Add a CommandButton, a Label, and a ListBox control to Form1. Adjust the width of the Label control so that it is the same as the width of the form.
4. Add the following code in the General Declarations section of Form1:

   Option Explicit
   
   Dim fso As New FileSystemObject
   Dim fld As Folder
   
   Private Sub Command1_Click()
      Dim nDirs As Long, nFiles As Long, lSize As Currency
      Dim sDir As String, sSrchString As String
      sDir = InputBox("Type the directory that you want to search for", _
                      "FileSystemObjects example", "C:\")
      sSrchString = InputBox("Type the file name that you want to search for", _
                      "FileSystemObjects example", "vb.ini")
      MousePointer = vbHourglass
      Label1.Caption = "Searching " & vbCrLf & UCase(sDir) & "..."
      lSize = FindFile(sDir, sSrchString, nDirs, nFiles)
      MousePointer = vbDefault
      MsgBox Str(nFiles) & " files found in" & Str(nDirs) & _
             " directories", vbInformation
      MsgBox "Total Size = " & lSize & " bytes"
   End Sub
   
   Private Function FindFile(ByVal sFol As String, sFile As String, _
      nDirs As Long, nFiles As Long) As Currency
      Dim tFld As Folder, tFil As File, FileName As String
      
      On Error GoTo Catch
      Set fld = fso.GetFolder(sFol)
      FileName = Dir(fso.BuildPath(fld.Path, sFile), vbNormal Or _
                     vbHidden Or vbSystem Or vbReadOnly)
      While Len(FileName) <> 0
         FindFile = FindFile + FileLen(fso.BuildPath(fld.Path, _
         FileName))
         nFiles = nFiles + 1
         List1.AddItem fso.BuildPath(fld.Path, FileName)  ' Load ListBox
         FileName = Dir()  ' Get next file
         DoEvents
      Wend
      Label1 = "Searching " & vbCrLf & fld.Path & "..."
      nDirs = nDirs + 1
      If fld.SubFolders.Count > 0 Then
         For Each tFld In fld.SubFolders
            DoEvents
            FindFile = FindFile + FindFile(tFld.Path, sFile, nDirs, nFiles)
         Next
      End If
      Exit Function
   Catch:  FileName = ""
          Resume Next
   End Function
   					

5. Run the project, and then click Command1.
6. Type the directory and the file name to search for. Notice that when each file is found, the file name is added to the list box. When the process is complete, the number of files that are found is displayed in a message box. The total size of the files is also displayed.

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Troubleshooting

• Some files and directories, such as System Volume Information on Microsoft Windows XP, cause an access violation if an application tries to access them. The error handling code stops looking in a directory when a problem occurs. You must use a different approach if you must have a more robust workaround.
• If you use a file filter (such as *.*), a large number of files may be returned. The ListBox control can only contain a limited number of characters. When that limit is reached, no more entries are added to the list box.
• This code sample was tested by using version 5.6.0.6626 of the Microsoft Scripting Runtime (Scrrun.dll). If problems occur, you may have to download a newer version of this file.

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