抽象和封装的区别?

封装和抽象之间的确切区别是什么?

当前回答

抽象或封装并不严格要求信息隐藏。信息可能会被忽略，但不一定要隐藏。

封装是一种将事物视为单一事物的能力，即使它可能由许多复杂的部分或思想组成。例如，我可以说我坐在一把“椅子”上，而不是指这把椅子上的许多不同部分，每个部分都有特定的设计和功能，它们精确地组合在一起，目的是让我的屁股舒适地离地板几英尺远。

Abstraction is enabled by encapsulation. Because we encapsulate objects, we can think about them as things which relate to each other in some way rather than getting bogged down in the subtle details of internal object structure. Abstraction is the ability to consider the bigger picture, removed from concern over little details. The root of the word is abstract as in the summary that appears at the top of a scholarly paper, not abstract as in a class which can only be instantiated as a derived subclass.

I can honestly say that when I plop my butt down in my chair, I never think about how the structure of that chair will catch and hold my weight. It's a decent enough chair that I don't have to worry about those details. So I can turn my attention toward my computer. And again, I don't think about the component parts of my computer. I'm just looking at a part of a webpage that represents a text area that I can type in, and I'm communicating in words, barely even thinking about how my fingers always find the right letters so quickly on the keyboard, and how the connection is ultimately made between tapping these keys and posting to this forum. This is the great power of abstraction. Because the lower levels of the system can be trusted to work with consistency and precision, we have attention to spare for greater work.

2013-08-26 16:58:20

其他回答

我试图在抽象和封装之间画一条线，根据我的观点，抽象更多的是概念性的东西，而封装是抽象实现的一种。因为一个人可以隐藏数据而不封装，例如使用私有常数或变量;所以我们可以用数据隐藏进行封装，但数据隐藏并不总是封装。在下面这段代码中，我试图描述这些概念的最简单形式。

    // Abstraction
    interface IOperation
    {
        int SquareNumber();
    }

    public class Operation
    {
        // Data hiding
        private int number;

        public Operation(int _number)
        {
            this.number = _number;
        }

        // Encapsulation
        public int SquareNumber()
        {
            return number * number;
        }
    }

在行动,

IOperation obj = new Operation(2); 
// obj.number  <--- can't access because hidden from world using private access modifier but not encapsulated. 
obj.SquareNumber(); // cannot access internal logic to calculate square because logic is hidden using encapsulation.

2017-04-18 07:21:13

抽象是对用户隐藏无用的数据封装是将数据绑定到一个胶囊(类)中。我认为封装是我们实现抽象的方式。

2011-07-06 11:55:13

我读得越多，就越困惑。所以，我的理解是:

封装:

我们通常从外面看到手表，它的组件被封装在它的身体里。我们对不同的操作有某种控制。这种隐藏细节和公开控制(例如设置时间)的方式就是封装。

抽象:

到目前为止，我们一直在谈论手表。但我们没有具体说明是哪种手表。可以是数字的，也可以是模拟的，可以是手用的，也可以是墙用的。有很多可能性。我们所知道的是，这是一块手表，它显示时间，这是我们唯一感兴趣的东西，时间。这种隐藏细节和公开通用特性或用例的方法就是抽象。

2021-10-18 18:51:07

抽象:以一种简化的/不同的方式来呈现事物的想法，这种方式要么更容易理解和使用，要么更切合实际。

考虑一个发送电子邮件的类……它使用抽象来向你展示自己作为某种信使，所以你可以调用emailSender。发送(邮件,收件人)。它的实际功能——选择POP3 / SMTP、调用服务器、MIME转换等等，都被抽象了出来。你只看到你的信使。

封装:保护和隐藏对象私有的数据和方法的思想。它更多的是让某样东西独立且万无一失。