Display detailed version information about the .NET framework installed

AboutFramework.cs

using System;
using Microsoft.Win32;

namespace AboutFramework
{
    class Program
    {
        static void Main(string[] args)
        {
            GetVersionFromRegistry();

            Console.WriteLine();

            Get45or451FromRegistry();

            Console.WriteLine();

            GetUpdateHistory();

            Console.WriteLine();
            Console.Write("Press any key to continue . . .");
            Console.ReadKey(true);
            Console.WriteLine();
        }

        private static void GetVersionFromRegistry()
        {
            // Opens the registry key for the .NET Framework entry.
            using (RegistryKey ndpKey =
                RegistryKey.OpenRemoteBaseKey(RegistryHive.LocalMachine, "").
                OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
            {
                // As an alternative, if you know the computers you will query are running .NET Framework 4.5 
                // or later, you can use:
                // using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, 
                // RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\NET Framework Setup\NDP\"))
                foreach (string versionKeyName in ndpKey.GetSubKeyNames())
                {
                    if (versionKeyName.StartsWith("v"))
                    {

                        RegistryKey versionKey = ndpKey.OpenSubKey(versionKeyName);
                        string name = (string)versionKey.GetValue("Version", "");
                        string sp = versionKey.GetValue("SP", "").ToString();
                        string install = versionKey.GetValue("Install", "").ToString();
                        if (install == "") //no install info, must be later.
                            Console.WriteLine(versionKeyName + "  " + name);
                        else
                        {
                            if (sp != "" && install == "1")
                            {
                                Console.WriteLine(versionKeyName + "  " + name + "  SP" + sp);
                            }

                        }
                        if (name != "")
                        {
                            continue;
                        }
                        foreach (string subKeyName in versionKey.GetSubKeyNames())
                        {
                            RegistryKey subKey = versionKey.OpenSubKey(subKeyName);
                            name = (string)subKey.GetValue("Version", "");
                            if (name != "")
                                sp = subKey.GetValue("SP", "").ToString();
                            install = subKey.GetValue("Install", "").ToString();
                            if (install == "") //no install info, must be later.
                                Console.WriteLine(versionKeyName + "  " + name);
                            else
                            {
                                if (sp != "" && install == "1")
                                {
                                    Console.WriteLine("  " + subKeyName + "  " + name + "  SP" + sp);
                                }
                                else if (install == "1")
                                {
                                    Console.WriteLine("  " + subKeyName + "  " + name);
                                }
                            }
                        }
                    }
                }
            }
        }

        private static void Get45or451FromRegistry()
        {
            using (RegistryKey ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey("SOFTWARE\\Microsoft\\NET Framework Setup\\NDP\\v4\\Full\\"))
            {
                if (ndpKey != null && ndpKey.GetValue("Release") != null)
                {
                    Console.WriteLine("Version: " + CheckFor45DotVersion((int)ndpKey.GetValue("Release")));
                }
                else
                {
                    Console.WriteLine("Version 4.5 or later is not detected.");
                }
            }
        }

        // Checking the version using >= will enable forward compatibility, 
        // however you should always compile your code on newer versions of
        // the framework to ensure your app works the same.
        private static string CheckFor45DotVersion(int releaseKey)
        {
            // Update from https://msdn.microsoft.com/en-us/library/hh925568(v=vs.110).aspx
            if (releaseKey >= 394802)
            {
                return "4.6.2 or later";
            }
            if (releaseKey >= 394254)
            {
                return "4.6.1 or later";
            }
            if (releaseKey >= 393295)
            {
                return "4.6 or later";
            }
            if ((releaseKey >= 379893))
            {
                return "4.5.2 or later";
            }
            if ((releaseKey >= 378675))
            {
                return "4.5.1 or later";
            }
            if ((releaseKey >= 378389))
            {
                return "4.5 or later";
            }
            // This line should never execute. A non-null release key should mean
            // that 4.5 or later is installed.
            return "No 4.5 or later version detected";
        }

        // From https://msdn.microsoft.com/en-us/library/hh925567(v=vs.110).aspx
        private static void GetUpdateHistory()
        {
            using (RegistryKey baseKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(@"SOFTWARE\Microsoft\Updates"))
            {
                foreach (string baseKeyName in baseKey.GetSubKeyNames())
                {
                    if (baseKeyName.Contains(".NET Framework") || baseKeyName.StartsWith("KB") || baseKeyName.Contains(".NETFramework"))
                    {

                        using (RegistryKey updateKey = baseKey.OpenSubKey(baseKeyName))
                        {
                            string name = (string)updateKey.GetValue("PackageName", "");
                            Console.WriteLine(baseKeyName + "  " + name);
                            foreach (string kbKeyName in updateKey.GetSubKeyNames())
                            {
                                using (RegistryKey kbKey = updateKey.OpenSubKey(kbKeyName))
                                {
                                    name = (string)kbKey.GetValue("PackageName", "");
                                    Console.WriteLine("  " + kbKeyName + "  " + name);

                                    if (kbKey.SubKeyCount > 0)
                                    {
                                        foreach (string sbKeyName in kbKey.GetSubKeyNames())
                                        {
                                            using (RegistryKey sbSubKey = kbKey.OpenSubKey(sbKeyName))
                                            {
                                                name = (string)sbSubKey.GetValue("PackageName", "");
                                                if (name == "")
                                                    name = (string)sbSubKey.GetValue("Description", "");
                                                Console.WriteLine("    " + sbKeyName + "  " + name);

                                            }
                                        }
                                    }
                                }
                            }
                        }
                    }
                }
            }
        }
    }
}