Registry reader debugger

debugger.ps1

function Get-ComPortNames {
    param (
        [string]$VendorID,
        [string]$ProductID
    )

    $pattern = "^VID_$VendorID.PID_$ProductID"
    $rx = New-Object System.Text.RegularExpressions.Regex($pattern, [System.Text.RegularExpressions.RegexOptions]::IgnoreCase)
    $comports = @()
    $rk1 = [Microsoft.Win32.Registry]::LocalMachine
    $rootKey = "SYSTEM\CurrentControlSet\Enum"
    "Root: $rootKey" | Out-File output.txt -Append
    
    $rk2 = $rk1.OpenSubKey($rootKey)
    if ($rk2 -ne $null) {
        foreach ($childKey in $rk2.GetSubKeyNames()) {
            "`t$childKey" | Out-File output.txt -Append
            $rk3 = $rk2.OpenSubKey($childKey)
            if ($rk3 -ne $null) {
                foreach ($grandChildKey in $rk3.GetSubKeyNames()) {
                    "`t`t$grandChildKey" | Out-File output.txt -Append
                    if ($rx.IsMatch($grandChildKey)) {
                        $rk4 = $rk3.OpenSubKey($grandChildKey)
                        if ($rk4 -ne $null) {
                            foreach ($greatGrandChildKey in $rk4.GetSubKeyNames()) {
                                "`t`t`t$greatGrandChildKey" | Out-File output.txt -Append
                                $rk5 = $rk4.OpenSubKey($greatGrandChildKey)
                                if ($rk5 -ne $null) {
                                    "`t`t`t`tDevice Parameters" | Out-File output.txt -Append
                                    $rk6 = $rk5.OpenSubKey("Device Parameters")
                                    if ($rk6 -ne $null) {
                                        "`t`t`t`t`tPortName" | Out-File output.txt -Append
                                        $portName = $rk6.GetValue("PortName")
                                        if ($portName -ne $null) {
                                            "`t`t`t`t`t`t$portName" | Out-File output.txt -Append
                                            $comports += $portName
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
    return $comports
}

$ports = Get-ComPortNames -VendorID "0B00" -ProductID "0084"
foreach ($port in $ports) {
    "Port: $port" | Out-File output.txt -Append
}

main.cs

using Microsoft.Win32;
using System;
using System.Collections.Generic;
using System.Text.RegularExpressions;

namespace ComPortDebugger
{
    internal class Program
    {
        static void Main(string[] args)
        {
            var ports = GetComPortNames("0B00", "0084");

            foreach (var port in ports)
            {
                Console.WriteLine("Port: " + port);
            }

            Console.Read();
        }

        private static List<string> GetComPortNames(string VID, string PID)
        {
            string pattern = string.Format("^VID_{0}.PID_{1}", VID, PID);
            Regex _rx = new Regex(pattern, RegexOptions.IgnoreCase);
            List<string> comports = new List<string>();
            RegistryKey rk1 = Registry.LocalMachine;
            var rootKey = "SYSTEM\\CurrentControlSet\\Enum";
            Console.WriteLine("Root: " + rootKey);
            RegistryKey rk2 = rk1.OpenSubKey(rootKey);
            foreach (string childKey in rk2.GetSubKeyNames())
            {   Console.WriteLine("\t" + childKey);
                RegistryKey rk3 = rk2.OpenSubKey(childKey);
                foreach (string grandChildKey in rk3.GetSubKeyNames())
                {
                    Console.WriteLine("\t\t" + grandChildKey);
                    if (_rx.Match(grandChildKey).Success)
                    {
                        RegistryKey rk4 = rk3.OpenSubKey(grandChildKey);
                        foreach (string greatGrandChildKey in rk4.GetSubKeyNames())
                        {
                            Console.WriteLine("\t\t\t" + greatGrandChildKey);
                            RegistryKey rk5 = rk4.OpenSubKey(greatGrandChildKey);

                            Console.WriteLine("\t\t\t\tDevice Parameters");
                            RegistryKey rk6 = rk5.OpenSubKey("Device Parameters");

                            Console.WriteLine("\t\t\t\t\tPortName");
                            var portName = rk6.GetValue("PortName");
                            Console.WriteLine("\t\t\t\t\t\t" + portName);
                            comports.Add((string)portName);
                        }
                    }
                }
            }
            return comports;
        }
    }
}