functions/Get-DbaClientAlias.ps1

function Get-DbaClientAlias {
    <#
    .SYNOPSIS
        Gets any SQL Server alias for the specified server(s)
 
    .DESCRIPTION
        Gets SQL Server alias by reading HKLM:\SOFTWARE\Microsoft\MSSQLServer\Client
 
    .PARAMETER ComputerName
        The target computer where the alias has been created
 
    .PARAMETER Credential
        Allows you to login to remote computers using alternative credentials
 
    .PARAMETER EnableException
        By default, when something goes wrong we try to catch it, interpret it and give you a friendly warning message.
        This avoids overwhelming you with "sea of red" exceptions, but is inconvenient because it basically disables advanced scripting.
        Using this switch turns this "nice by default" feature off and enables you to catch exceptions with your own try/catch.
 
    .NOTES
        Tags: Alias
        Author: Chrissy LeMaire (@cl), netnerds.net
 
        Website: https://dbatools.io
        Copyright: (c) 2018 by dbatools, licensed under MIT
        License: MIT https://opensource.org/licenses/MIT
 
    .LINK
        https://dbatools.io/Get-DbaClientAlias
 
    .EXAMPLE
        PS C:\> Get-DbaClientAlias
 
        Gets all SQL Server client aliases on the local computer
 
    .EXAMPLE
        PS C:\> Get-DbaClientAlias -ComputerName workstationx
 
        Gets all SQL Server client aliases on Workstationx
 
    .EXAMPLE
        PS C:\> Get-DbaClientAlias -ComputerName workstationx -Credential ad\sqldba
 
        Logs into workstationx as ad\sqldba then retrieves all SQL Server client aliases on Workstationx
 
    .EXAMPLE
        PS C:\> 'Server1', 'Server2' | Get-DbaClientAlias
 
        Gets all SQL Server client aliases on Server1 and Server2
 
#>

    [CmdletBinding()]
    param (
        [Parameter(ValueFromPipeline)]
        [DbaInstanceParameter[]]$ComputerName = $env:COMPUTERNAME,
        [PSCredential]$Credential,
        [Alias('Silent')]
        [switch]$EnableException
    )

    process {
        foreach ($computer in $ComputerName) {
            $scriptblock = {

                function Get-ItemPropertyValue {
                    param (
                        [parameter()]
                        [String]$Path,
                        [parameter()]
                        [String]$Name
                    )
                    (Get-ItemProperty -LiteralPath $Path -Name $Name).$Name
                }

                $basekeys = "HKLM:\SOFTWARE\WOW6432Node\Microsoft\MSSQLServer", "HKLM:\SOFTWARE\Microsoft\MSSQLServer"

                foreach ($basekey in $basekeys) {

                    if ((Test-Path $basekey) -eq $false) {
                        Write-Warning "Base key ($basekey) does not exist. Quitting."
                        continue
                    }

                    $client = "$basekey\Client"

                    if ((Test-Path $client) -eq $false) {
                        continue
                    }

                    $connect = "$client\ConnectTo"

                    if ((Test-Path $connect) -eq $false) {
                        continue
                    }

                    if ($basekey -like "*WOW64*") {
                        $architecture = "32-bit"
                    } else {
                        $architecture = "64-bit"
                    }

                    # "Get SQL Server alias for $ComputerName for $architecture"
                    $all = Get-Item -Path $connect
                    foreach ($entry in $all.Property) {
                        $value = Get-ItemPropertyValue -Path $connect -Name $entry
                        $clean = $value.Replace('DBNMPNTW,', '').Replace('DBMSSOCN,', '')
                        if ($value.StartsWith('DBMSSOCN')) { $protocol = 'TCP/IP' } else { $protocol = 'Named Pipes' }

                        [pscustomobject]@{
                            ComputerName   = $env:COMPUTERNAME
                            NetworkLibrary = $protocol
                            ServerName     = $clean
                            AliasName      = $entry
                            AliasString    = $value
                            Architecture   = $architecture
                        }
                    }
                }
            }

            try {
                Invoke-Command2 -ComputerName $computer -Credential $Credential -ScriptBlock $scriptblock -ErrorAction Stop |
                    Select-DefaultView -Property ComputerName, Architecture, NetworkLibrary, ServerName, AliasName
            } catch {
                Stop-Function -Message "Failure" -ErrorRecord $_ -Target $computer -Continue
            }
        }
    }
}