Creating A Nested Directory

Even though this code is relatively simple, it’s surprising to see the number of major applications on the shelves that fail to correctly handle this scenario.

The code shown below consists of two functions. The bValDIR function is needed because in Visual Basic, if you try to create a directory using the MkDir function that already exists, MkDir will generate an error.

Code

Sub MakeDir (sDirName As String)

Dim iMouseState As Integer
Dim iNewLen As Integer
Dim iDirLen As Integer

    'Get Mouse State

     iMouseState = Screen.MousePointer

     'Change Mouse To Hour Glass

     Screen.MousePointer = 11

     'Set Start Length To Search For [\]

     iNewLen = 4

     'Add [\] To Directory Name If Not There

     If Right$(sDirName, 1) <> "\" Then

           sDirName = sDirName + "\"

     End If

     'Create Nested Directory

     Do While Not bValDir(sDirName)

           iDirLen = InStr$(iNewLen, sDirName, "\")

           If Not bValDir(Left$(sDirName, iDirLen)) Then

                 MkDir Left$(sDirName, iDirLen - 1)

           End If

           iNewLen = iDirLen + 1

     Loop

     'Leave The Mouse The Way You Found It

     Screen.MousePointer = iMouseState

End Sub

Function bValDir (sIncoming As String) As Integer

Dim iCheck As String
Dim iErrResult As Integer

    On Local Error GoTo ValDirError

     If Right$(sIncoming, 1) <> "\" Then

           sIncoming = sIncoming + "\"

     End If

     iCheck = Dir$(sIncoming)

     If iErrResult = 76 Then

           bValDir = False

     Else

           bValDir = True

     End If 
Exit Function

ValDirError:

     Select Case Err

           Case Is = 76

                 iErrResult = Err

                 Resume Next

           Case Else

     End Select

End Function

 

This tip is reprinted from the VB Tips & Tricks Volume 1 book.
Parts of this tip was submitted by: David McCarter

Compatible With All Versions of Visual Basic
Applies To Disk Directory