Converters class - Register all your data-type conversions in a single place

using System;
using System.Linq;
using System.Collections.Generic;
using ConfigurableConvertTest.GenericConverters;
using System.Diagnostics;

namespace ConfigurableConvertTest
{
    class Program
    {
        private const int COUNT = 10000000;
        static void Main(string[] args)
		{
			Converters.GlobalRegister<string, int>((value) => int.Parse(value));
			Converters.GlobalSearching += ToArrayConverter.SearchingConverterHandler;

			var converters = Converters.LocalInstance;

            // If you comment the next line, a converter from string to nullable will be
            // found thanks to the FromTypeDescriptorConverter. But such default converter
            // throws an exception if the string is filled with spaces.
            converters.Searching += StringToNullableConverter.SearchingConverterHandler;

            converters.Searching += FromTypeDescriptorConverter.SearchingConverterHandler;
			var converter = converters.Get<string, int>();
            if (converter("57") != 57)
				throw new Exception("Error to convert string to int.");

            if (GlobalConvert.ChangeType<string>(57) != "57")
                throw new Exception("Error on GlobalConvert.");

            converters.Searching += EnumToUnderlyingConverter.SearchingConverterHandler;
            converters.Searching += UnderlyingToEnumConverter.SearchingConverterHandler;

            using (var isolatedConverters = new Converters(ConvertersMode.Isolated))
            {
                if (isolatedConverters.TryGet<AttributeTargets, int>() != null)
                    throw new Exception("Isolated converters was not really isolated.");

                if (isolatedConverters.TryGet<string, int>() != null)
                    throw new Exception("Isolated converters was not really isolated.");
            }

            using (var basedOnGlobalConverters = new Converters(ConvertersMode.BasedOnGlobal))
            {
                if (basedOnGlobalConverters.TryGet<AttributeTargets, int>() != null)
                    throw new Exception("BasedOnGlobal converters found a previous local registered converter.");

                if (basedOnGlobalConverters.TryGet<string, int>() == null)
                    throw new Exception("BasedOnGlobal converters did not find a global registered converter.");
            }

            var enumToIntConverter = converters.Get<AttributeTargets, int>();
            int moduleAsInt = enumToIntConverter(AttributeTargets.Module);
			if (moduleAsInt != (int)AttributeTargets.Module)
				throw new Exception("Error converting an enum to its underlying type.");

            var stringToNullableIntConverter = converters.Get<string, int?>();
            if (stringToNullableIntConverter(" ").HasValue)
                throw new Exception("Error converting a space string to a nullable int.");

            if (stringToNullableIntConverter("57").GetValueOrDefault() != 57)
                throw new Exception("Error converting a 57 string to a nullable int.");

			var intToEnumConverter = converters.Get<int, AttributeTargets>();
			var moduleEnum = intToEnumConverter(moduleAsInt);
			if (moduleEnum != AttributeTargets.Module)
				throw new Exception("Error converting from int (underlying type) to AttributeTargets (enum).");

			var list = new List<int>();
			list.Add(57);
			list.Add(58);
			
			var listToArrayConverter = converters.Get<List<int>, int[]>();
			var array = listToArrayConverter(list);
            if (!array.SequenceEqual(list))
                throw new Exception("The array conversion did a bad job.");

			converters.Searching += AlreadyCompatibleConverter.SearchingConverterHandler;
			var intToObjectConverter = converters.Get<int, object>();
			var result = intToObjectConverter(57);

            var intStringConverter = converters.Get<int, string>();
            if (intStringConverter(57) != "57")
				throw new Exception("Error to convert int to string.");

            var untypedConvert = converters.CastedTryGet(typeof(int), typeof(string));
            var untypedResult = untypedConvert(57);
            if (!untypedResult.Equals("57"))
                throw new Exception("The untyped conversion did a bad job.");

			Stopwatch stopwatch = new Stopwatch();

			stopwatch.Reset();
			stopwatch.Start();
			for(int i=0; i<COUNT; i++)
			{
				var intValue = enumToIntConverter(AttributeTargets.Event);
				var enumValue = intToEnumConverter(intValue);
				if (enumValue != AttributeTargets.Event)
					throw new ApplicationException("Error when converting from enum to int and again to enum");
			}
			stopwatch.Stop();
			Console.WriteLine("Converting enum/int using Converters delegates: " + stopwatch.Elapsed);

			stopwatch.Reset();
			stopwatch.Start();
            var enumToIntConverterUntyped = converters.CastedGet<AttributeTargets, int>();
			var intToEnumConverterUntyped = converters.CastedGet<int, AttributeTargets>();
			for(int i=0; i<COUNT; i++)
			{
				var intValue = enumToIntConverterUntyped(AttributeTargets.Event);
				var enumValue = (AttributeTargets)intToEnumConverterUntyped(intValue);
				if (enumValue != AttributeTargets.Event)
					throw new ApplicationException("Error when converting from enum to int and again to enum");
			}
			stopwatch.Stop();
			Console.WriteLine("Converting enum/int using Converters casted delegates: " + stopwatch.Elapsed);

			stopwatch.Reset();
			stopwatch.Start();
			for(int i=0; i<COUNT; i++)
			{
				var intValue = Convert.ToInt32(AttributeTargets.Event);
				
				// I first tried this, but it does not work:
				//var enumValue = (AttributeTargets)Convert.ChangeType(intValue, typeof(AttributeTargets));
				//
				// So, the right code is this:
				var enumValue = (AttributeTargets)Enum.ToObject(typeof(AttributeTargets), intValue);
				
				if (enumValue != AttributeTargets.Event)
					throw new ApplicationException("Error when converting from enum to int and again to enum");
			}
			stopwatch.Stop();
			Console.WriteLine("Converting enum/int using Convert and Enum.ToObject: " + stopwatch.Elapsed);

			Console.WriteLine();
            Console.WriteLine("All the test conversions where done without errors.");
            Console.WriteLine("If you want to see something use the WPF application or debug the code.");
            Console.WriteLine("Press [Enter] to exit.");
            Console.ReadLine();

		}
    }
}