Get-sjWifiPassword

Get-sjWifiPassword-Function.ps1

function Get-sjWifiPassword {

  <#
    .SYNOPSIS
      Gets the password of one or more wireless networks.
    .DESCRIPTION
      This function uses the netsh command to retrieve the password of one or more wireless networks
      that have been previously connected to the device. It returns an object with the network name and the password.
    .PARAMETER NetworkName
      Specifies the name of the wireless network to get the password for. If not specified, it will
      get the passwords for all wireless networks that have been previously connected to the device.
      This parameter accepts pipeline input by property name or by value.
    .EXAMPLE
      Get-sjWifiPassword
      This example gets the passwords for all wireless networks that have been previously connected
      to the device.
    .EXAMPLE
      Get-sjWifiPassword -NetworkName SETUP-D413
      This example gets the password for the wireless network named SETUP-D413.
    .EXAMPLE
      'setup-d413' | Get-sjWifiPassword
      This example gets the password for the wireless network named setup-d413 using pipeline input
      by value.
    .INPUTS
      System.String
    .OUTPUTS
      PSCustomObject
    .NOTES
      This function requires netsh command ($env:SystemRoot\System32\netsh.exe) to be in the proper
      location. It will throw an error if netsh command is not found or not accessible.
  #>

  param (
    [parameter(ValueFromPipeline, ValueFromPipelineByPropertyName)]
    [string[]]$NetworkName
  )

  begin {
    if ((Get-Command -Name 'netsh').Source -ne "$env:SystemRoot\System32\netsh.exe") {
      throw 'netsh command is not in the proper location'
    }
  }

  process {
    if (-not ($PSBoundParameters.ContainsKey('NetworkName'))) {
      $NetworkName = (
        netsh wlan show profile | Select-String ' : (.+)$'
      ).Matches.Groups.Where({ $_.Name -eq 1 }).Value
    }
    foreach ($item in $NetworkName) {
      [PSCustomObject]@{
        Network  = $item
        Password = (
          netsh wlan show profile name="$item" key=clear |
            Select-String 'Key Content\s+:\s(.+)$'
        ).Matches.Groups.Where({ $_.Name -eq 1 }).Value
      }
    }
  }

  end {}
} #end function Get-sjWifiPassword

# test cases
# Get-sjWifiPassword
# Get-sjWifiPassword -NetworkName SETUP-D413
# Get-sjWifiPassword -NetworkName trash
# Get-sjWifiPassword -NetworkName (1..4)
# 'setup-d413' | Get-sjWifiPassword
# 1..4 | Get-sjWifiPassword