Code example that demonstrates a fundamental flaw in Enum.TryParse<T>().

Enum.TryParse.Fail.cs

// Code example that demonstrates a fundamental flaw in Enum.TryParse<T>().

using System;
using System.Linq;
					
public class Program
{
	public static void Main()
	{
		var values = new[] {
			/*
			// These strings are all parsed successfully by Enum.TryParse<System.DayOfWeek>(), as expected.
			"Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday", "Sunday",	
			"0", "1", "2", "3", "4", "5", "6",
			*/
			
			/*
			// These strings are all parsed successfully by Enum.TryParse<System.DayOfWeek>() -IF- case-insensitivity is enabled, as expected.
			"MoNday", "TuEsday", "WeDnesday", "ThUrsday", "FrIday", "SaTurday", "SuNday",
			*/
			
			// These strings are all parsed successfully by Enum.TryParse<System.DayOfWeek>(), even though they shouldn't be.
			"55"
		};
		
		var results = values.Select(x => 
		{
			var tryParseResult = Enum.TryParse<System.DayOfWeek>(x, true, out var parsedEnum);
			
			return new {
				String = x,
				TryParseResult = tryParseResult,
				ParsedEnum = parsedEnum
			};
		});
		
		foreach (var result in results.OrderBy(x => x.TryParseResult)) 
		{
			Console.WriteLine($@"TryParse<System.DayOfWeek>(""{result.String}"") = {result.TryParseResult}");
			if (result.TryParseResult) Console.WriteLine($@"ParsedEnum = {result.ParsedEnum}");
			Console.WriteLine();
		}
	}
}