Question

I have a text file that I need to go through line by line and delete any text that is in quotation marks and does not match one of the following values:

• 192.168.10.1
• 192.168.11.1
• 192.168.12.1
• 192.168.13.1

My initial file would look something like this:

IPADDRESS “192.168.10.1” “192.168.11.1” “192.168.12.1” “192.168.13.1” “10.0.0.1”
IPADDRESS “192.168.10.1” “192.168.11.1” “127.0.0.1” “192.168.12.1” “192.168.13.1”

and I would like my output to be similar to the following:

IPADDRESS “192.168.10.1” “192.168.11.1” “192.168.12.1” “192.168.13.1”
IPADDRESS “192.168.10.1” “192.168.11.1” “192.168.12.1” “192.168.13.1”

I’ve experimented with using the -replace option, regular expressions, using the trim option, using a filter, using the -match option, to varying degrees of success, but I keep hitting a brick wall…

Answer 1

You can split the line, remove unwanted parts with a regex pattern and assemble back the line:

Get-Content ip.txt | Where-Object {$_} | Foreach-Object {
   $line=$_.Split()
   $line[0] + ' ' + ($line -match '"192\.168\.1[0-3]\.1"') -join ' '
}