.NET: What Version Is On the Target Server

I'm upgrading .NET (legacy 4.*) applications on multiple unfamiliar servers.  This includes needing to know if the currently installed framework meets my requirements.  Instead of fumbling through the actual registry, I can pasted this C# snippet into a console app and all is good:

REFERENCE: https://docs.microsoft.com/en-us/dotnet/framework/migration-guide/how-to-determine-which-versions-are-installed

	using System;
	using Microsoft.Win32;
	public class GetDotNetVersion
	{
	public static void Main()
	{
	Get45PlusFromRegistry();
	}
	private static void Get45PlusFromRegistry()
	{
	const string subkey = @"SOFTWARE\Microsoft\NET Framework Setup\NDP\v4\Full\";
	using (var ndpKey = RegistryKey.OpenBaseKey(RegistryHive.LocalMachine, RegistryView.Registry32).OpenSubKey(subkey))
	{
	if (ndpKey != null && ndpKey.GetValue("Release") != null) {
	Console.WriteLine($".NET Framework Version: {CheckFor45PlusVersion((int) ndpKey.GetValue("Release"))}");
	}
	else {
	Console.WriteLine(".NET Framework Version 4.5 or later is not detected.");
	}
	}
	// Checking the version using >= enables forward compatibility.
	string CheckFor45PlusVersion(int releaseKey)
	{
	if (releaseKey >= 528040)
	return "4.8 or later";
	if (releaseKey >= 461808)
	return "4.7.2";
	if (releaseKey >= 461308)
	return "4.7.1";
	if (releaseKey >= 460798)
	return "4.7";
	if (releaseKey >= 394802)
	return "4.6.2";
	if (releaseKey >= 394254)
	return "4.6.1";
	if (releaseKey >= 393295)
	return "4.6";
	if (releaseKey >= 379893)
	return "4.5.2";
	if (releaseKey >= 378675)
	return "4.5.1";
	if (releaseKey >= 378389)
	return "4.5";
	// This code 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";
	}
	}
	}
	// This example displays output like the following:
	// .NET Framework Version: 4.6.1

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