by Chris Wilson (9 Submissions)
Category: Files/File Controls/Input/Output
Compatability: Visual Basic 3.0
Difficulty: Advanced
Date Added: Wed 3rd February 2021
Rating: 
(2 Votes)
There are many methods you can use to return certain parts of a fully qualified path to a file. Here is the SHORTEST and FASTEST way to 1) return just the path, 2) return just the filename, and 3) change the extension of a filename. The code is so short that it is probably faster to keep it inline than to create additional functions. (I've done so here to better illustrate the parameters.
Assumes
I've intentionally left out doing any checks for a valid path in order to show the simplicity of the code.
VBcodersPublic Sub PathTest
' Return just the path "c:\test\"
' TRUE strips the backslash, FALSE retains it
Debug.Print JustPath("c:\test\myfile.txt", "\", True)
' Return just the filename "myfile.txt"
' Change "\" to "/" to handle UNIX or URL pathnames!
Debug.Print JustFile("c:\test\myfile.txt", "\")
' Change the extension to "bak" and return "c:\test\myfile.bak"
Debug.Print ChangeExt("c:\test\myfile.txt", "bak")
' Change the extension and return just the filename "myfile.bak"
' Change "\" to "/" to handle UNIX or URL pathnames!
Debug.Print JustFile(ChangeExt("c:\test\myfile.txt", "bak"), "\")
End Sub
Public Function JustPath(ByVal filepath As String, ByVal dirchar As String, ByVal stripbs As Integer) As String
' Returns just the path
' TRUE evaluates to -1, FALSE evaluates to 0 so
' simple addition is all we need at the end to remove the slash
JustPath = Mid$(filepath, 1, InStrRev(filepath, dirchar) + stripbs)
End Function
Public Function JustFile(ByVal filepath As String, ByVal dirchar As String) As String
' Returns just the filename
JustFile = Mid$(filepath, InStrRev(filepath, dirchar) + 1)
End Function
Public Function ChangeExt(ByVal filepath As String, ByVal newext As String) As String
' Changes the extension
ChangeExt = Mid$(filepath, 1, InStrRev(filepath, ".")) & newext
End Function