csharp http://stackoverflow.com/questions/5915740/how-to-convert-a-typecode-to-an-actual-type/357029

Posted 2021-05-12

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
using System.Diagnostics;

namespace SwitchVsDictionary
{
    static class Program
    {
        static void Main(string[] args)
        {
            var typeCodes = TypeCodeToTypeMap.Keys.ToList();
            int iterations = 10000000;
            
            Benchmark(() =>
            {
                foreach(var typeCode in typeCodes)
                {
                    typeCode.ToTypeDict();
                }
            }, iterations);

            Benchmark(() =>
            {
                foreach (var typeCode in typeCodes)
                {
                    typeCode.ToTypeSwitch();
                }
            }, iterations);
        }

        /// <summary>
        /// Table that maps TypeCode to it's corresponding Type.
        /// </summary>
        static IReadOnlyDictionary<TypeCode, Type> TypeCodeToTypeMap = new Dictionary<TypeCode, Type>
        {
            { TypeCode.Boolean, typeof(bool) },
            { TypeCode.Byte, typeof(byte) },
            { TypeCode.Char, typeof(char) },
            { TypeCode.DateTime, typeof(DateTime) },
            { TypeCode.DBNull, typeof(DBNull) },
            { TypeCode.Decimal, typeof(decimal) },
            { TypeCode.Double, typeof(double) },
            { TypeCode.Empty, null },
            { TypeCode.Int16, typeof(short) },
            { TypeCode.Int32, typeof(int) },
            { TypeCode.Int64, typeof(long) },
            { TypeCode.Object, typeof(object) },
            { TypeCode.SByte, typeof(sbyte) },
            { TypeCode.Single, typeof(Single) },
            { TypeCode.String, typeof(string) },
            { TypeCode.UInt16, typeof(UInt16) },
            { TypeCode.UInt32, typeof(UInt32) },
            { TypeCode.UInt64, typeof(UInt64) }
        };

        /// <summary>
        /// Convert a TypeCode ordinal into it's corresponding Type instance.
        /// </summary>
        public static Type ToTypeDict(this TypeCode code)
        {
            return TypeCodeToTypeMap[code];
        }

        public static Type ToTypeSwitch(this TypeCode code)
        {
            switch (code)
            {
                case TypeCode.Boolean:
                    return typeof(bool);

                case TypeCode.Byte:
                    return typeof(byte);

                case TypeCode.Char:
                    return typeof(char);

                case TypeCode.DateTime:
                    return typeof(DateTime);

                case TypeCode.DBNull:
                    return typeof(DBNull);

                case TypeCode.Decimal:
                    return typeof(decimal);

                case TypeCode.Double:
                    return typeof(double);

                case TypeCode.Empty:
                    return null;

                case TypeCode.Int16:
                    return typeof(short);

                case TypeCode.Int32:
                    return typeof(int);

                case TypeCode.Int64:
                    return typeof(long);

                case TypeCode.Object:
                    return typeof(object);

                case TypeCode.SByte:
                    return typeof(sbyte);

                case TypeCode.Single:
                    return typeof(Single);

                case TypeCode.String:
                    return typeof(string);

                case TypeCode.UInt16:
                    return typeof(UInt16);

                case TypeCode.UInt32:
                    return typeof(UInt32);

                case TypeCode.UInt64:
                    return typeof(UInt64);
            }

            return null;
        }

        /// <summary>
        /// From http://stackoverflow.com/questions/1622440/benchmarking-method-calls-in-c-sharp
        /// </summary>
        private static void Benchmark(Action act, int iterations)
        {
            GC.Collect();
            Stopwatch sw = Stopwatch.StartNew();
            for (int i = 0; i < iterations; i++)
            {
                act.Invoke();
            }
            sw.Stop();
            Console.WriteLine(sw.ElapsedMilliseconds);
        }
    }
}