remove nul characters from text file using vbs - vbscript

Question

I have text files that are approximately 6MB in size. There are some lines that contain the NULL (Chr(0))character that I would like to remove.
I have two methods to do this: using Asc()=0 but this takes approximately 50s to complete, the other method uses InStr (line, Chr(0)) =0 (fast ~ 4sec)but the results remove vital info from the lines which contain the NULL characters.
First line of text file as example:
##MMCIBN.000NULL7NULL076059NULL7653NULL1375686349NULL2528NULL780608NULL10700NULL\NULL_NC_ACT.DIR\CFG_RESET.INI
First method (works but VERY slow)
function normalise (textFile )
Set fso = CreateObject("Scripting.FileSystemObject")
writeTo = fso.BuildPath(tempFolder, saveTo & ("\Output.arc"))
Set objOutFile = fso.CreateTextFile(writeTo)
Set objFile = fso.OpenTextFile(textFile,1)
Do Until objFile.AtEndOfStream
strCharacters = objFile.Read(1)
If Asc(strCharacters) = 0 Then
objOutFile.Write ""
nul = true
Else
if nul = true then
objOutFile.Write(VbLf & strCharacters)
else
objOutFile.Write(strCharacters)
end if
nul = false
End If
Loop
objOutFile.close
end function
The output looks like this:
##MMCIBN.000
7
076059
7653
1375686349
2528
780608
10700
\
_NC_ACT.DIR\CFG_RESET.INI
Second method code:
filename = WScript.Arguments(0)
Set fso = CreateObject("Scripting.FileSystemObject")
sDate = Year(Now()) & Right("0" & Month(now()), 2) & Right("00" & Day(Now()), 2)
file = fso.BuildPath(fso.GetFile(filename).ParentFolder.Path, saveTo & "Output " & sDate & ".arc")
Set objOutFile = fso.CreateTextFile(file)
Set f = fso.OpenTextFile(filename)
Do Until f.AtEndOfStream
line = f.ReadLine
If (InStr(line, Chr(0)) > 0) Then
line = Left(line, InStr(line, Chr(0)) - 1) & Right(line, InStr(line, Chr(0)) + 1)
end if
objOutFile.WriteLine line
Loop
f.Close
but then the output is:
##MMCIBN.000\CFG_RESET.INI
Can someone please guide me how to remove the NULLS quickly without losing information. I have thought to try and use the second method to scan for which line numbers need updating and then feed this to the first method to try and speed things up, but quite honestly I have no idea where to even start doing this!
Thanks in advance...

Answer 1

It looks like the first method is just replacing each NULL with a newline. If that's all you need, you can just do this:
Updated:
OK, sounds like you need to replace each set of NULLs with a newline. Let's try this instead:
strText = fso.OpenTextFile(textFile, 1).ReadAll()
With New RegExp
.Pattern = "\x00+"
.Global = True
strText = .Replace(strText, vbCrLf)
End With
objOutFile.Write strText
Update 2:
I think the Read/ReadAll methods of the TextStream class are having trouble dealing with the mix of text and binary data. Let's use an ADO Stream object to read the data instead.
' Read the "text" file using a Stream object...
Const adTypeText = 2
With CreateObject("ADODB.Stream")
.Type = adTypeText
.Open
.LoadFromFile textFile
.Charset = "us-ascii"
strText = .ReadText()
End With
' Now do our regex replacement...
With New RegExp
.Pattern = "\x00+"
.Global = True
strText = .Replace(strText, vbCrLf)
End With
' Now write using a standard TextStream...
With fso.CreateTextFile(file)
.Write strText
.Close
End With

Answer 2

I tried this method (update2) for reading a MS-Access lock file (Null characters terminated strings in 64 byte records) and the ADODB.Stream didn't want to open an already in use file. So I changed that part to :
Set fso = CreateObject("Scripting.FileSystemObject")
Set f = fso.GetFile(Lfile)
z = f.Size
set ts = f.OpenAsTextStream(ForReading, 0) 'TristateFalse
strLog = ts.Read(z)
ts.Close
set f = nothing
' replace 00 with spaces
With New RegExp
.Pattern = "\x00+"
.Global = True
strLog = .Replace(strLog, " ")
End With
' read MS-Access computername and username
for r = 1 to len(strLog) step 64
fnd = trim(mid(strLog,r, 32)) & ", " & trim(mid(strLog,r+32, 32)) & vbCrLf
strRpt = strRpt & fnd
next