ConvertTo-CN

function ConvertTo-CN {
    <#
    .SYNOPSIS
        Converts a DistinguishedName to its equivalent CanonicalName format.

    .DESCRIPTION
        Converts a DistinguishedName value to its corresponding CannonicalName value.

    .PARAMETER  DistinguishedName
        The DistinguishedName value to examine. This can be supplied implicitly by piping an object that has a DistinguishedName property.

    .PARAMETER  InputObject
        The object(s) to process. This parameter is typically supplied by piping objects to the function.

    .PARAMETER  PropertyName
        The name of the property to add (as a NoteProperty) to the InputObject. This property will be set to the CanonicalName value calculated.

    .EXAMPLE
        'CN=Harden\, Marsha Gay,OU=Users,DC=fabrikan,DC=com' | ConvertTo-CN
      fabrikan.com/Users/Harden, Marsha Gay

    .EXAMPLE
        $ADOrgUnitObject | ConvertTo-CN -PropertyName CN
      OU=TestOU,OU=Testing,DC=fabrikan,DC=com

    .INPUTS
        System.String, PSObject

    .OUTPUTS
        System.String, PSObject

    .NOTES
        The CanonicalName value is calculated using only string manipulation; ActiveDirectory is not checked so the object to which the DistinguishedName refers need not exist.

      #>
    [CmdletBinding(DefaultParameterSetName = 'None')]
    [Alias('ConvertTo-CanonicalName', 'ConvertFrom-DN', 'ConvertFrom-DistinguishedName')]
    [OutputType([string], ParameterSetName = "None")]
    [OutputType([PSObject], ParameterSetName = "InputObject")]
    Param (
        [Parameter(Mandatory, Position = 0, ValueFromPipeline, ValueFromPipelineByPropertyName, ParameterSetName = 'None')][Alias('DN')][string[]]$DistinguishedName,
        [Parameter(Mandatory, ValueFromPipeline, ParameterSetName = 'InputObject')][PSObject[]]$InputObject,
        [Parameter(Mandatory, ParameterSetName = 'InputObject')][string]$PropertyName = 'DN'
    )
    begin {
        # Write-Host ($PSBoundParameters | Out-String); Write-Host $PSCmdlet.ParameterSetName
        [boolean]$PipelineInput = -not $PSBoundParameters.ContainsKey("DistinguishedName")
        function CCN {
            [CmdletBinding()]
            Param ([Parameter(Position = 0, Mandatory)][string]$DN)
            [System.Collections.ArrayList]$CN = @(); [System.Collections.ArrayList]$DC = @()
            [System.Collections.ArrayList]$Items = @((($DN -replace '\\,', '##COMMA##') -split ',') | % {
                    $_ = $_ -replace '\\([,\#+<>;"=])', '$1'
                    $_ = $_ -replace '\A\\\s|\\\s\z', ' '
                    $_ = $_ -replace '([\/])', '\$1'
                    while ($_ -match '(.*?)(?<!\\)\\([a-f\d]{2})(.*)') {
                        $_ = $Matches[1] + ([CHAR][CONVERT]::ToInt16($Matches[2], 16)) + $Matches[3]
                    }
                    $_
                })
            [void]$Items.Reverse()
            while (($Items.Count -gt 0) -and ($Items[0] -match '\ADC=')) {
                [void]$DC.Add(($Items[0] -replace '\ADC='))
                [void]$Items.RemoveAt(0)
            }
            [void]$DC.Reverse()
            while ($Items.Count -gt 0) {
                [void]$CN.Add(($Items[0] -replace '\A(DC|OU|CN)='))
                [void]$Items.RemoveAt(0)
            }
            (($DC -join '.') + '/' + (($CN -join '/') -replace '##COMMA##', ','))
        }
    }
    process {
        # Write-Host ($PSBoundParameters | Out-String); Write-Host $PSCmdlet.ParameterSetName
        if ($PipelineInput) {
            if ($PSBoundParameters.ContainsKey('PropertyName')) {
                $CN = CCN -DN $InputObject.DistinguishedName
                $InputObject[0] | Add-Member -NotePropertyName $PropertyName -NotePropertyValue $CN -Force -PassThru
            } else {
                CCN -DN $DistinguishedName[0]
            }
        } else {
            foreach ($DN in $DistinguishedName) {
                CCN -DN $DN
            }
        }
    }
} # ConvertTo-CN