Read files in subfolders - vbscript

Question

I'm trying to make a script that we can output a specific string ino a files from a list of files in different subfolders.
My script works but onl for one directory. I need some help to make it works with subfolders
Const ForReading = 1
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set folder = objFSO.GetFolder("D:\vbs\logs\") ' here i have loads of subfolders with *.txt
Set outfile = objFSO.CreateTextFile("D:\vbs\ok\test.txt") ' my output file
for each file in folder.Files
Set testfile = objFSO.OpenTextFile(file.path, ForReading)
Do While Not testfile.AtEndOfStream
If instr (testfile.readline, "central") then ' i output every lines where there is the word "central"
outfile.writeline testfile.readline
End If
if instr (testfile.readline, "version") then ' i use this to parse my output file to get a indication between every files read
num = testfile.readline
mag = Split(num)
elseif testfile.AtEndOfStream = true then
outfile.writeline "Shop " & mag(4)
end if
Loop
testfile.close
next
outfile.close

Answer 1

See this answer to a similar question for a folder recursion example.
One remark about your existing code, though: each call of the ReadLine method reads the next line from the file, so something like this:
If instr (testfile.readline, "central") then
outfile.writeline testfile.readline
End If
will not output the line containing the word "central" (as your comments say), but the line after that line.
If you want to output the line containing the word you're checking for, you have to store the read line in a variable and continue with that variable:
line = testfile.ReadLine
If InStr(line, "central") Then
outfile.WriteLine line
End If

Answer 2

I would encapsulate your entire For...Each block into a new subroutine and then add a new For...Each block to capture all subFolders in the parent folder. I added that functionality to your script, see below.
Const ForReading = 1
Const Start_Folder = "D:\vbs\logs\" ' here i have loads of subfolders with *.txt
Set objFSO = CreateObject("Scripting.FileSystemObject")
Set outfile = objFSO.CreateTextFile("D:\vbs\ok\test.txt") ' my output file
'Call the Search subroutine to start the recursive search.
Search objFSO.GetFolder(Start_Folder)
'Close the outfile after all folders have been searched
outfile.Close
Sub Search(sDir)
for each file in sDir.Files
Set testfile = objFSO.OpenTextFile(file.path, ForReading)
Do While Not testfile.AtEndOfStream
If instr (testfile.readline, "central") then ' i output every lines where there is the word "central"
outfile.writeline testfile.readline
End If
if instr (testfile.readline, "version") then ' i use this to parse my output file to get a indication between every files read
num = testfile.readline
mag = Split(num)
elseif testfile.AtEndOfStream = true then
outfile.writeline "Shop " & mag(4)
end if
Loop
testfile.close
next
'Find EACH SUBFOLDER.
For Each subFolder In sDir.SubFolders
'Call the Search subroutine to start the recursive search on EACH SUBFOLDER.
Search objFSO.GetFolder(subFolder.Path)
Next
End Sub