LINQ training session 3 - Generic homework

gistfile1.cs

using System;
using Microsoft.VisualStudio.TestTools.UnitTesting;
using LinqSession3_GenericSample;
using System.Text;

namespace UnitTestLinqSession3
{
    [TestClass]
    public class UnitTest1
    {
        [TestMethod]
        public void Test_Person()
        {
            var target = new EntityHelper();

            var entity = new Person { Id = 91, Age = 18, Name = "Joey" };

            target.LogPkey<Person>(entity);

            var resultMessage = target.GetMessage();

            var sb = new StringBuilder();

            sb.AppendLine(string.Format("Pkey name:{0}, value:{1}", "Id", "91"));

            var expected = sb.ToString();

            Assert.AreEqual(expected, resultMessage);
        }

        [TestMethod]
        public void Test_Order()
        {
            var target = new EntityHelper();

            var entity = new Order { Id = 1, Price = 100 };

            target.LogPkey<Order>(entity);

            var resultMessage = target.GetMessage();

            Assert.AreEqual(string.Empty, resultMessage);
        }
    }

    public class Person
    {
        [Pkey]
        public int Id { get; set; }

        public int Age { get; set; }

        public string Name { get; set; }
    }

    public class Order
    {        
        public int Id { get; set; }

        public int Price { get; set; }        
    }
}

gistfile2.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace LinqSession3_GenericSample
{
    public class PkeyAttribute : Attribute
    {

    }
}

gistfile3.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;

namespace LinqSession3_GenericSample
{
    public class EntityHelper
    {
        private StringBuilder _message = new StringBuilder();

        // Todo:  adding function :  LogPkey() 

        public string GetMessage()
        {
            return this._message.ToString();
        }
    }
}