Get All Shared Printers with WMI and PowerShell

I whipped up this handy dandy script yesterday for work, and I think it makes a good simple example script, so I'm posting it here:

# Finds all servers that are hosting printers.

#

# Author: Tojo2000 

#

# Note: Requires a text file with one server per line named 'winserv.txt'.

$credential = Get-Credential

$servers = gc winserv.txt | sort

echo "ServerName`tShareName`tName`tDriverName`tStatus" > .\printers.txt

foreach ($server in $servers) {

  echo $server

  $ping = gwmi Win32_PingStatus -Filter "address = `"$server`""

  if ((!$ping.StatusCode) -and (!$ping.PrimaryAddressResolutionStatus)) {

    $printers = gwmi -Credential $credential -ComputerName $server -class Win32_Printer -Filter 'Shared = "True"'

    foreach ($printer in $printers) {

      if ($printer) {

        $output = $server, $printer.ShareName, $printer.Name, $printer.DriverName, $printer.Status

        echo ($output | Join-String2 "`t") >> .\printers.txt

      }

    }

  }

}

__________________________________________

# Join-String2

# Args:

#   $join_string: the string to paste between each element of the string array

#

# Returns:

#   The resulting string to the pipeline

function global:Join-String2 ([string]$join_string) {

  $output = '';

  $input_array = @($input);

  

  foreach ($string in $input_array[0..($input_array.Length - 2)]) {

    $output += $string;

  $output += $join_string;

  }

  $output += $input_array[-1];

  

  Write-Output $output;

}

There are a couple of things worthy of note here.  The Get-Credential cmdlet pops up a prompt to enter a username and password and stores it as a SecureString This is vastly more secure than storing the string in your script or typing it in to the console window.  Get-WMIObject, like many cmdlets, has a -Credential option that takes a credential as an input and runs the cmdlet under that account.  You can also specify a username here, and Get-Credential will be invoked to prompt you for the password.

The Join-String2 function is because there is already a cmdlet that is part of the PowerShell Comunity Extensions called Join-String, but apparently it freaks out if any of the values being printed are null, so I created a function that does a basic join.

The -Filter option of Get-WMIObject is basically just the "where clause" of the wmi query, which is to say that

gwmi Win32_Printer -Filter 'Shared = "True"'

is the same thing as

gwmi -Query 'Select * From Win32_Printer Where Shared = "True"'

It's just a lot more PowerShell-ish and a little less verbose.