实体之间的深拷贝

public static T Copy<T>(T RealObject)
        {
            using (Stream objectStream = new MemoryStream())
            {
                //利用 System.Runtime.Serialization序列化与反序列化完成引用对象的复制     
                IFormatter formatter = new BinaryFormatter();
                formatter.Serialize(objectStream, RealObject);
                objectStream.Seek(0, SeekOrigin.Begin);
                return (T)formatter.Deserialize(objectStream);
            }
        }