Need a VB-Script that read a txt-file and only the lines that are new since last time

Question

Hi,
I need help to write a VB script that read all new lines since the last time.
For example:  The script reads the textfile at specific time, then 10 minutes later the script read the file again, and it should now only read the lines that are new since last time. Anyone that has such a script in your scriptingbox?
cheers!
DocHo
Doc

Answer 1

Based on the excellent idea by Pegasus, where is a VBScript solution. I use a separate file to save the last line count read from the file, then each time the file is read I update the line count. Only lines after the last count are output by the program:
Option Explicit
Dim strFile, objFSO, objFile, strCountFile, objCountFile, strLine, lngCount, lngLine
Const ForReading = 1
Const ForWriting = 2
Const OpenAsASCII = 0
Const CreateIfNotExist = True
' Specify input file to be read.
strFile = "c:\Scripts\Example.log"
' Specify file with most recent line count.
strCountFile = "c:\Scripts\Count.txt"
' Open the input file for reading.
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set objFile = objFSO.OpenTextFile(strFile, ForReading)
' Check if the line count file exists.
If (objFSO.FileExists(strCountFile) = False) Then
    ' Initial count is 0, so all lines are read.
    lngCount = 0
Else
    ' Open the line count file.
    Set objCountFile = objFSO.OpenTextFile(strCountFile, ForReading)
    ' Read the most recent line count.
    Do Until objCountFile.AtEndOfStream
        lngCount = CLng(objCountFile.ReadLine)
    Loop
End If
' Read the input file.
lngLine = 0
Do Until objFile.AtEndOfStream
    ' Count lines.
    lngLine = lngLine + 1
    strLine = objFile.ReadLine
    If (lngLine >= lngCount) Then
        ' Output the line.
        Wscript.Echo strLine
    End If
Loop
' Close all files.
objFile.Close
If (lngCount > 0) Then
    objCountFile.Close
End If
' Ignore last line of the file if it is blank.
If (strLine = "") Then
    lngLine = lngLine - 1
End If
' Save the new line count.
Set objCountFile = objFSO.OpenTextFile(strCountFile, _
    ForWriting, CreateIfNotExist, OpenAsASCII)
objCountFile.WriteLine CStr(lngLine + 1)
objCountFile.Close
Richard Mueller - MVP Directory Services