Sequential Guid Generator

GuidGenerator.cs

using System;
using System.Runtime.InteropServices;

namespace eConduct.Extensions
{
    public static class GuidGenerator
    {
        [DllImport("rpcrt4.dll", SetLastError = true)]
        private static extern int UuidCreateSequential(out Guid guid);

        const int RPC_S_OK = 0;

        public static Guid NewSequentialGuid()
        {
            Guid guid;
            int result = UuidCreateSequential(out guid);
            if (result == RPC_S_OK)
                return guid;
            else
                return Guid.NewGuid();
        }
    }
}

// Test 
using Microsoft.VisualStudio.TestTools.UnitTesting;
using System;
using System.Collections.Generic;
using System.Linq;

namespace eConduct.Extensions.Tests
{
    [TestClass]
    public class GuidGeneratorTests
    {
        [TestMethod]
        public void GuidGenerator_NewSequentialGuid()
        {
            var guids = new List<Tuple<int, Guid>>(); 
            
            for (var i = 0; i < 1000; i++)
            {
                guids.Add(new Tuple<int, Guid>(i, GuidGenerator.NewSequentialGuid())); 
            }

            guids = guids.OrderBy(c => c.Item2).ToList();

            for (int i = 0; i < guids.Count; i++)
            {
                Assert.AreEqual(i, guids[i].Item1);
            }
        }
    }
}