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) Chrissy LeMaire, clemaire@gmail.com
            License: MIT https://opensource.org/licenses/MIT
 
        .LINK
            https://dbatools.io/Get-DbaClientAlias
 
        .EXAMPLE
            Get-DbaClientAlias
 
            Gets all SQL Server client aliases on the local computer
 
        .EXAMPLE
            Get-DbaClientAlias -ComputerName workstationx
 
            Gets all SQL Server client aliases on Workstationx
 
        .EXAMPLE
            '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
            }
        }
    }
}