如何从C#调用这个Delphi函数？

library MyDelphiLibrary;

uses
  System.SysUtils;

function Add(a: Integer; b: Integer): Integer; stdcall;
begin
  Result := a + b;
end;

exports
  Add;

using System;
using System.Runtime.InteropServices;

namespace MyCSharpProject
{
    class Program
    {
        [DllImport("MyDelphiLibrary.dll", CallingConvention = CallingConvention.StdCall)]
        public static extern int Add(int a, int b);

        static void Main(string[] args)
        {
            int result = Add(5, 3);
            Console.WriteLine("5 + 3 = " + result);
        }
    }
}