从评论更新：

我需要通过自己的参数来扩展LINQ到SQL类和不想要触碰任何生成的类。任何更好的suggestes的欢迎。但我也不想这样做所有的属性分配的所有时间，如果再在LINQ到SQL类正在发生变化。因此，如果vstudio生成新的属性的一类，我有我自己的扩展属性分开，而新的类本身innerited

I need to extend linq-to-sql classes by own parameters and dont want to touch any generated classes. Any better suggestes are welcome. But I also don't want to do all attributes assignments all time again if the linq-to-sql classes are changing. so if vstudio generates new attribute to a class i have my own extended attributes kept separate, and the new innerited from the class itself

原题：

我不知道这是否是可能的。 我有一类汽车类mycar从类车延。 类mycar也有一个字符串列表。唯一区别。

i'm not sure if it's possible. I have a class car and a class mycar extended from class car. Class mycar has also a string list. Only difference.

我怎么能现在施放任何汽车对象为mycar对象没有指派所有 用手属性每个。像：

How can i cast now any car object to a mycar object without assigning all attributes each by hand. Like:

Car car = new Car();

MyCar mcar = (MyCar) car;

或

MyCar mcar = new MyCar(car);

或不过，我可以延长汽车用自己的变量，并不需要做总是

or however i can extend car with own variables and don't have to do always

Car car = new Car();
MyCar mcar = new MyCar();
mcar.name = car.name;
mcar.xyz = car.xyz;
...

感谢。

推荐答案

在回答关于这个问题的意见，对LINQ到SQL类生成的部分。这意味着你可以有声明为部分相同的类名独立code文件添加你需要的额外的属性。

In response to your comment on the question, the Linq-To-Sql classes are generated as partial. This means you can have separate code files with the same class names declared as partial to add the extra properties you want.

例如。你的灵到SQL设计器类将是：

E.g. Your Ling-To-Sql designer class will be:

public partial class Car
{
     .... lots of auto generated stuff ....
}

您可以有自己独立的文件（在同一个项目）呼吁Car.cs：

You can have your own separate file (in the same project) called Car.cs:

public partial class Car
{
     public MyCustomStuff{ get; set; }
}

和两班将被合并到一起。只要确保他们在同一个命名空间。

And the two classes will be merged together. Just make sure they are in the same namespace.