Entity Framework 4.0/如何拼接来自日期和时间的字符串

using System;
using System.Data.Entity;

public class MyEntity
{
    public int Id { get; set; }
    public DateTime MyDateTime { get; set; }
}

public class MyDbContext : DbContext
{
    public DbSet<MyEntity> MyEntities { get; set; }
}

public class Program
{
    public static void Main()
    {
        using (var context = new MyDbContext())
        {
            // 创建一个新的实体对象
            var entity = new MyEntity
            {
                MyDateTime = DateTime.Now
            };

            // 将实体对象添加到数据库中
            context.MyEntities.Add(entity);
            context.SaveChanges();

            // 从数据库中检索实体对象
            var retrievedEntity = context.MyEntities.Find(entity.Id);

            // 将日期和时间拼接为字符串
            var dateString = retrievedEntity.MyDateTime.ToString("yyyy-MM-dd");
            var timeString = retrievedEntity.MyDateTime.ToString("HH:mm:ss");
            var concatenatedString = dateString + " " + timeString;

            Console.WriteLine(concatenatedString);
        }
    }
}