CODEWITHSUNDEEP
powershellcsv
metho
metho

Reputation: 73

Use PowerShell to add dash symbols to a list of MAC addresses in a CSV file

I am looking for a script that would add "-" after every two digits of a MAC Address. There is already a script here that fixes this. 

$macs = Get-Content C:\Users\metho\Desktop\mac.txt
$output = foreach ($mac in $macs){
    $mac.insert(2,"-").insert(5,"-").insert(8,"-").insert(11,"-").insert(14,"-")
}
$output | Out-File C:\Users\nmetho\Desktop\mac1.txt

The problem I have is that I am using a CSV file that contains four columns and therefore the above script does not work for me. 

Description, MacAddress, IPAddess, Location

CJ0001, 00351AC0353C, 192.168.2.5, Room1

I am looking to modify only the MacAddress field so that I get the "Mac Address" in this format 00-35-1A-C0-35-3C.

Can I use this script to achieve what I am looking for or do I need to start from scratch?

Upvotes: 1

Views: 2774

Answers (2)

TechSpud
TechSpud

Reputation: 3518

This should work:

$macs | ForEach-Object {
  Select Description, @{Name='MacAddress'; Expression={ ($_.MacAddress -split '([A-Z0-9]{2})' | Where-Object {$_}) -join '-' }}, IPAddess, Location
}

Breaking the expression down:

{ `
  ( `
  $_.MacAddress -split '([A-Z0-9]{2})' ` # regex split the mac address up every two alpha-numeric chars
  | Where-Object {$_} `                  # filter to only return non-blank splits
  ) `
  -join '-'                              # join the 2-char pairs with a '-'
}

EDIT

And here is a complete example, mixing your code, with mine, to input a file, then output it:

# remove comment before -Header if no header
$csv = Import-Csv -Path C:\Users\metho\Desktop\Macadd.csv # -Header Description, MacAddress, IPAddess, Location
$csv | ForEach-Object { Select HostName, @{Name='MacAddress'; Expression={ ($_.MacAddress -split '([A-Z0-9]{2})' | Where-Object {$_}) -join '-' }} } |
  Export-Csv -Path C:\Users\metho\Desktop\MacAdd_v1.csv -NoTypeInformation

Although, this can be simplified, by not using variables, like this:

  Import-CSV C:\Users\metho\Desktop\Macadd.csv |
  ForEach-Object { Select HostName, @{Name='MacAddress'; Expression={ ($_.MacAddress -split '([A-Z0-9]{2})' | Where-Object {$_}) -join '-' }} } |
  Export-CSV C:\Users\metho\Desktop\MacAdd_v1.csv -NoTypeInformation

Upvotes: 1

Mark Wragg
Mark Wragg

Reputation: 23355

This is tested and works. Per the discussion comments I've included a check for strings that aren't the expected length of a MAC address. This will also ensure it doesn't add further dashes if you run it subsequent times:

Import-CSV 'C:\Users\metho\Desktop\macadd.csv' | ForEach-Object {   
    If ($_.MacAddress.length -eq 12){
        $_.MacAddress = $_.MacAddress.insert(2,"-").insert(5,"-").insert(8,"-").insert(11,"-").insert(14,"-")
    } Else {
        Write-Warning "The MAC Address $($_.MacAddress) is not 12 characters"
    }
    Write-Output $_
} | Export-CSV 'C:\Users\metho\Desktop\macadd_v1.csv' -NoTypeInformation

Upvotes: 2

Related Questions