String equals benchmarks

stringEqualsBenchmarks.cs

using BenchmarkDotNet.Attributes;
using BenchmarkDotNet.Columns;
using BenchmarkDotNet.Configs;
using BenchmarkDotNet.Jobs;
using BenchmarkDotNet.Reports;
using System;

namespace BenchmarkDotNet.Samples
{
    [MemoryDiagnoser]
    [Config(typeof(Config))]
    [SimpleJob(RuntimeMoniker.Net80)]
    [HideColumns(Column.Job, Column.RatioSD, Column.AllocRatio)]
    public class StringComparisonBenchmarks
    {
        private class Config : ManualConfig
        {
            public Config()
            {
                SummaryStyle =
                    SummaryStyle.Default.WithRatioStyle(RatioStyle.Percentage);
            }
        }

        private string str1 = "HELLO WORLD";
        private string str2 = "hello world";

        [Benchmark(Baseline = true)]
        public bool Equals_OrdinalIgnoreCase() => string.Equals(str1, str2, StringComparison.OrdinalIgnoreCase);

        [Benchmark]
        public bool Compare_OrdinalIgnoreCase() => string.Compare(str1, str2, StringComparison.OrdinalIgnoreCase) == 0;

        [Benchmark]
        public bool ToLower() => str1.ToLower() == str2.ToLower();

        [Benchmark]
        public bool ToUpper() => str1.ToUpper() == str2.ToUpper();
    }
}