Add a folder to the Environment PATH

AddtoPath.ps1

<#
.SYNOPSIS
  Add a folder to the Environment PATH

.DESCRIPTION
  This script will take a folder as parameter and edit the system PATH variable for all users, appending the specified folder to the existing PATH

.PARAMETER AddedLocation
    Full path of location to add. Spcify with " " around it please

.PARAMETER LogPath
    Path to the log file

.INPUTS
  Parameters above

.OUTPUTS
  Script output will be written to $LogPath

.NOTES
  Version:        1.0
  Author:         Omer Barel
  Creation Date:  January 14th, 2017
  Purpose/Change: Initial script development
  
.EXAMPLE
  AddtoPath -AddedLocation "C:\My New Location\Sub folder with spaces allowed" -LogPath "C:\Logs\ScriptLog.log"
#>


#----------------------------------------------------------[Declarations]----------------------------------------------------------

#Parameters
[CmdletBinding()]
Param(
  [Parameter(Mandatory=$true,Position=1)]
  [string]$AddedLocation,

  [Parameter(Mandatory=$true,Position=1)]
  [string]$LogPath
)

#---------------------------------------------------------[Initialisations & Functions]--------------------------------------------------------

#Set Error Action to Silently Continue
$ErrorActionPreference = "SilentlyContinue"

Function Write-Log {
  <#
      .Synopsis
          Write-Log writes a message to a specified log file with the current time stamp.
      .DESCRIPTION
          The Write-Log function is designed to add logging capability to other scripts.
          In addition to writing output and/or verbose you can write to a log file for
          later debugging.
      .NOTES
          Created by: Jason Wasser @wasserja
          Modified: 11/24/2015 09:30:19 AM  

          Changelog:
              * Code simplification and clarification - thanks to @juneb_get_help
              * Added documentation.
              * Renamed LogPath parameter to Path to keep it standard - thanks to @JeffHicks
              * Revised the Force switch to work as it should - thanks to @JeffHicks

          To Do:
              * Add error handling if trying to create a log file in a inaccessible location.
              * Add ability to write $Message to $Verbose or $Error pipelines to eliminate
              duplicates.
      .PARAMETER Message
          Message is the content that you wish to add to the log file. 
      .PARAMETER Path
          The path to the log file to which you would like to write. By default the function will 
          create the path and file if it does not exist. 
      .PARAMETER Level
          Specify the criticality of the log information being written to the log (i.e. Error, Warning, Informational)
      .PARAMETER NoClobber
          Use NoClobber if you do not wish to overwrite an existing file.
      .EXAMPLE
          Write-Log -Message 'Log message' 
          Writes the message to c:\Logs\PowerShellLog.log.
      .EXAMPLE
          Write-Log -Message 'Restarting Server.' -Path c:\Logs\Scriptoutput.log
          Writes the content to the specified log file and creates the path and file specified. 
      .EXAMPLE
          Write-Log -Message 'Folder does not exist.' -Path c:\Logs\Script.log -Level Error
          Writes the message to the specified log file as an error message, and writes the message to the error pipeline.
      .LINK
          https://gallery.technet.microsoft.com/scriptcenter/Write-Log-PowerShell-999c32d0
  #>

  [CmdletBinding()]
  Param
  (
      [Parameter(Mandatory = $true,
          ValueFromPipelineByPropertyName = $true)]
      [ValidateNotNullOrEmpty()]
      [Alias("LogContent")]
      [string]$Message,

      [Parameter(Mandatory = $false)]
      [Alias('LogPath')]
      [string]$Path = 'C:\Logs\PowerShellLog.log',
      
      [Parameter(Mandatory = $false)]
      [ValidateSet("Error", "Warn", "Info")]
      [string]$Level = "Info",
      
      [Parameter(Mandatory = $false)]
      [switch]$NoClobber
  )

  Begin {
      # Set VerbosePreference to Continue so that verbose messages are displayed.
      $VerbosePreference = 'Continue'
  }
  Process {
      
      # If the file already exists and NoClobber was specified, do not write to the log.
      if ((Test-Path $Path) -AND $NoClobber) {
          Write-Error "Log file $Path already exists, and you specified NoClobber. Either delete the file or specify a different name."
          Return
      }

      # If attempting to write to a log file in a folder/path that doesn't exist create the file including the path.
      elseif (!(Test-Path $Path)) {
          Write-Verbose "Creating $Path."
          $NewLogFile = New-Item $Path -Force -ItemType File
      }

      else {
          # Nothing to see here yet.
      }

      # Format Date for our Log File
      $FormattedDate = Get-Date -Format "yyyy-MM-dd HH:mm:ss"

      # Write message to error, warning, or verbose pipeline and specify $LevelText
      switch ($Level) {
          'Error' {
              Write-Error $Message
              $LevelText = 'ERROR:'
          }
          'Warn' {
              Write-Warning $Message
              $LevelText = 'WARNING:'
          }
          'Info' {
              Write-Verbose $Message
              $LevelText = 'INFO:'
          }
      }
      
      # Write log entry to $Path
      "$FormattedDate $LevelText $Message" | Out-File -FilePath $Path -Append
  }
  End {
  }
}

#-----------------------------------------------------------[Execution]------------------------------------------------------------

Set-ExecutionPolicy -ExecutionPolicy Unrestricted -Force

Write-Log -Message "Starting Logging on computer $env:COMPUTERNAME" -Path $LogPath

$RegistyLocation = "Registry::HKLM\System\CurrentControlSet\Control\Session Manager\Environment"
$CurrentPath = (Get-ItemProperty -Path $RegistyLocation -Name PATH).Path
Write-Log -Message "Getting PATH location from Registry location $RegistryLocation" -Path $LogPath
Write-Log -Message "Current value in PATH is $CurrentPath" -Path $LogPath
Write-Log -Message "Building new PATH" -Path $LogPath
$NewPath = $CurrentPath + ';' + $AddedLocation
Write-Log -Message "Applying new PATH" -Path $LogPath
Set-ItemProperty -Path $RegistyLocation -Name PATH -Value $NewPath
$UpdatedPath = (Get-ItemProperty -Path $RegistyLocation -Name PATH).Path
Write-Log -Message "PATH is now set to $UpdatedPath" -Path $LogPath

Write-Log -Message "Script execution completed" -Path $LogPath