field or property

Program.cs

using System;
using System.Collections.Generic;
using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Configs;
using BenchmarkDotNet.Diagnosers;
using BenchmarkDotNet.Running;

namespace Benchmark
{
    class Program
    {
        static void Main()
        {
            var summary = BenchmarkRunner.Run<WeigherBenchmark>(DefaultConfig.Instance.With(new MemoryDiagnoser()));
        }
    }

    public class WeigherBenchmark
    {
        List<ObjToWeigh> _objs = new List<ObjToWeigh>();

        [Setup]
        public void Setup()
        {
            int objsCount = 500000;
            Random rng = new Random();

            for (int z = 0; z < objsCount; z++)
            {
                _objs.Add(new ObjToWeigh(rng.Next(200), rng.Next(200), rng.Next(200)));
            }
        }

        [Benchmark]
        public int TotalWeight()
        {
            int tot = 0;
            foreach (var o in _objs)
                tot += o.Metric1;
            return tot;
        }

        [Benchmark]
        public int TotalWeightByField_or_Prop()
        {
            const string propName = "Metric1";
            var propInfo = typeof(ObjToWeigh).GetProperty(propName);
            var fieldInfo = typeof(ObjToWeigh).GetField(propName);
            if (propInfo == null && fieldInfo == null)
                throw new Exception($"Invalid property {propName}");

            int tot = 0;
            foreach (var o in _objs)
            {
                if (propInfo != null)
                    tot += (int)propInfo.GetValue(o);
                else
                    tot += (int)fieldInfo.GetValue(o);
            }
            return tot;
        }

        [Benchmark]
        public int TotalWeightByField()
        {
            const string propName = "Metric1";

            var fieldInfo = typeof(ObjToWeigh).GetField(propName);
            if (fieldInfo == null)
                throw new Exception($"Invalid field {propName}");
            int tot = 0;
            foreach (var o in _objs)
            {
                tot += (int)fieldInfo.GetValue(o);
            }
            return tot;
        }
    }

    public class ObjToWeigh
    {
        public int Metric1;
        public int Metric2;
        public int Metric3;

        public ObjToWeigh(int m1, int m2, int m3)
        {
            Metric1 = m1;
            Metric2 = m2;
            Metric3 = m3;
        }

    }
}