Long File Names and Short File Names
Man, am I stupid.
Ok, everybody. (well, those of you who like to scroll through old
posts...)
I did not read the text of my referring document very well. (my fault... I
was in a hurry). To get the short path name of a file, you would use the
GetShortPathName API function (not hard at all) and I thought--when I
scanned the docs--that GetFullPathName was its complement. Not so.
GetFullPathName will take a filename and, if there is no path in front of
the file name, prepend the current path and drive, and if there *is* a path
in front, it will return the string unchanged, but give you a pointer to
the filename in the returned string. It does NO validation of file/path
names. (and, like Appleman said, is more trouble than its worth)
However, what we need is the complement to GetShortPathName. This,
according to the docs, is FindFirstFile. Go figure.
I apologize for the length of this code sample, but I didn't see an easy
way around it. Note that I did NOT do any playing with UNC names, so if
you're looking for them, you'll have to code for it.
1. Create a new project.
2. Place a CommandButton (Command1) on the default Form1.
3. Paste the code below into Form1's code window.
4. Run the program and click the button.
Private Const MAX_PATH = 260
Private Type FILETIME
dwLowDateTime As Long
dwHighDateTime As Long
End Type
Private 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
Private Declare Function FindFirstFile Lib "kernel32" Alias
"FindFirstFileA" (ByVal lpFileName As String, lpFindFileData As
WIN32_FIND_DATA) As Long
Private Declare Function GetShortPathName Lib "kernel32" Alias
"GetShortPathNameA" (ByVal lpszLongPath As String, ByVal lpszShortPath As
String, ByVal cchBuffer As Long) As Long
Private Sub Command1_Click()
Dim sShort As String
Dim sLong As String
sShort = GetShortName("c:\New Text Document.txt")
sLong = GetLongName(sShort)
Debug.Print "Short Name = " & sShort
Debug.Print "Long Name = " & sLong
End Sub
Public Function GetShortName(LongName As String) As String
Dim lpName As String
Dim cbName As Long
Dim rVal As Long
cbName = MAX_PATH
lpName = String$(cbName, 0)
rVal = GetShortPathName(LongName, lpName, cbName)
If rVal = 0 Then
GetShortName = ""
Else
GetShortName = Left$(lpName, rVal)
End If
End Function
Public Function GetLongName(ShortName As String) As String
Dim fd As WIN32_FIND_DATA
Dim strLongName As String, lpFileName As String, lpPathName As String
Dim rVal As Long
' Get the filename
rVal = FindFirstFile(ShortName, fd)
lpFileName = Left$(fd.cFileName, InStr(fd.cFileName, Chr$(0)) - 1)
' Get the rest of the path
lpPathName = Left$(ShortName, Len(ShortName) - (Len(fd.cAlternate) -
1))
If Len(lpPathName) > 2 Then
rVal = FindFirstFile(Left$(ShortName, Len(ShortName) -
(Len(fd.cAlternate) - 1)), fd)
lpPathName = Left$(fd.cFileName, InStr(fd.cFileName, Chr$(0)) - 1)
' Concatenate the drive, path and file.
GetLongName = Left$(ShortName, 2) & "\" & lpPathName & "\" &
lpFileName
Else
' Concatenate the drive and file.
GetLongName = lpPathName & "\" & lpFileName
End If
End Function
------------
Jim Houghtaling
email: hmm... no.
web: working on it (heh)
platform(s): Win95 os/r2, WinNT 4.0 sp3, VB5ee sp3
('till I get my page up go to VBNet...It's the best I've seen yet.)
http://home.sprynet.com/sprynet/rasanen/vbnet/default.htm
------------
It often shows an excellent command
of language to say nothing.
Quote:
> Thanks,
> I tried the GetShortPathName and GetFullPathName functions right away,
but
> did not have any success with them. The always return a blank string to
me.
> The Daniel Appelman book even says that GetFullPathName is difficult to
use
> in VB, but he doesn't give an example of how to use it right. Do you have
> any experience using these API functions successfully.
> Joe
