blocks|key|4833890|text|这些术语有两种不同的用法：|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4833891|4833892|临时使用：|unordered-list-item|4833893|4833894|-+Class:+Abstract+data+type+with+methods+and+fields.
-+Object:+Instance+of+a+class.
-+Variable:+Language-level+name+(i.e:+name+given+by+a+programmer)+for+some+piece+of+storage.
-+Datatype:+Type+that+a+variable+(or+some+unnamed+piece+of+storage)+can+have.|code-block|syntax|javascript|4833895|​|4833896|4833897|C/C%2B%2B标准用法(来自C标准，它不是面向对象的语言：|4833898|4833899|-+Object:+Some+piece+of+storage,+whether+it+has+a+name+or+not.
-+Object+of+Class+Type:+Some+piece+of+storage+whose+datatype+is+class(=struct).|4833900|4833901|entityMap^0|0|0|0|0|0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|W|8|@]|9|@]|A|$]]|$1|B|3|-4|5|6|7|X|8|@]|9|@]|A|$]]|$1|C|3|D|5|E|7|Y|8|@]|9|@]|A|$]]|$1|F|3|-4|5|6|7|Z|8|@]|9|@]|A|$]]|$1|G|3|H|5|I|7|10|8|@]|9|@]|A|$J|K]]|$1|L|3|M|5|6|7|11|8|@]|9|@]|A|$]]|$1|N|3|-4|5|6|7|12|8|@]|9|@]|A|$]]|$1|O|3|P|5|E|7|13|8|@]|9|@]|A|$]]|$1|Q|3|-4|5|6|7|14|8|@]|9|@]|A|$]]|$1|R|3|S|5|I|7|15|8|@]|9|@]|A|$J|K]]|$1|T|3|M|5|6|7|16|8|@]|9|@]|A|$]]|$1|U|3|-4|5|6|7|17|8|@]|9|@]|A|$]]]|V|$]]

There are two different uses of these terms:

<ul>
<li>Casual use:

<ul>
<li>Class: Abstract data type with methods and fields.</li>
<li>Object: Instance of a class.</li>
<li>Variable: Language-level name (i.e: name given by a programmer) for some piece of storage.</li>
<li>Datatype: Type that a variable (or some unnamed piece of storage) can have.</li>
</ul></li>
<li>C/C++ standard use (comes from the C standard, which isn't an Object-Oriented Language:

<ul>
<li>Object: Some piece of storage, whether it has a name or not.</li>
<li>Object of Class Type: Some piece of storage whose datatype is class(=struct).</li>
</ul></li>
</ul>

blocks|key|4833736|text|变量是具有直接名称的对象。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4833737|int+i;|code-block|syntax|javascript|4833738|I是一个变量，也是一个对象。|4833739|int*+p+=+new+int;|4833740|*p是对象，但不是变量。|4833741|类和类型几乎相同，除了类型包括像int这样的原始类型。实际上，它们是可互换的--以及变量/对象。C%2B%2B标准的实际情况是，很少有规则以不同的方式应用于类和类型，以及变量和对象。|4833742|entityMap^0|0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|Q|8|@]|9|@]|A|$]]|$1|B|3|C|5|D|7|R|8|@]|9|@]|A|$E|F]]|$1|G|3|H|5|6|7|S|8|@]|9|@]|A|$]]|$1|I|3|J|5|D|7|T|8|@]|9|@]|A|$E|F]]|$1|K|3|L|5|6|7|U|8|@]|9|@]|A|$]]|$1|M|3|N|5|6|7|V|8|@]|9|@]|A|$]]|$1|O|3|-4|5|6|7|W|8|@]|9|@]|A|$]]]|P|$]]

Variables are objects with direct names.

<pre><code>int i;
</code></pre>

i is a variable and an object.

<pre><code>int* p = new int;
</code></pre>

*p is an object but not a variable.

Classes and types are pretty much identical, except types includes primitive types like int. Realistically, they're pretty interchangable- as well as variable/object. The reality of the C++ Standard is that very few rules apply differently to classes than to types, and variables than to objects.

blocks|key|4833788|text|一个类可以看作是一组限定了作用域的函数和私有变量。对象是一个类的实例，例如，toyata可以是一个名为Car的类的对象实例。变量是一个标识符。它表示值和状态可以随时间变化的标识符。数据类型表示数据类型。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|4833789|例如，假设Car是一个类。然后声明：|4833790|Car+toyata;|code-block|syntax|javascript|4833791|具有类、数据类型、标识符(变量)和对象。|4833792|entityMap^0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|M|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|N|8|@]|9|@]|A|$]]|$1|D|3|E|5|F|7|O|8|@]|9|@]|A|$G|H]]|$1|I|3|J|5|6|7|P|8|@]|9|@]|A|$]]|$1|K|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|L|$]]

A class can be considered a group of scoped function and private variables.
A object is an instance of a class, for example toyata can be a object instance of a class called Car.
A variable is a identifier. It represents a identifier who's values and state can change in time
A datatype represents the type of data. 

For example, assume Car is a class. Then the statement:

<pre><code>Car toyata;
</code></pre>

Has a class, data-type, identifier(variable) and object.

blocks|key|2935724|text|数据类型是强烈指示某些数据的使用方式的方式(在强类型语言中，如c%2B%2B)。例如，int数据类型让您知道可以执行传统上与整数(整数)相关联的操作。当某事物的数据类型为char时，这让您知道可以像使用字符一样使用它(例如，字母表中的一个字母)。这两个是内置于该语言中的basic数据类型的示例。|type|unstyled|depth|inlineStyleRanges|offset|length|style|CODE|BOLD|entityRanges|data|2935725|类(通常是*)是一种组装某些数据的方式，并为其提供一个惟一的接口来访问和修改这些数据。与可以加减整数或除浮点数(无需截断)的方式相同，放入类中的函数决定了程序如何使用它。类似地，其他人创建的类提供了一个接口，以便您可以像使用整数一样使用这些类的对象。|2935726|变量是某些数据类型的单个实例。如果你有一些int+number+=+0;，那就是一个变量。这与“常量”形成了鲜明对比，即像const+double+pi+=+3.14159;这样不可修改的符号。|2935727|“对象”这个词可以被认为是模棱两可的--大多数时候，当人们使用“对象”这个词时，他们的意思是“一些class或struct的实例”。但有时，它被用来指代类。这可能会让人感到困惑，但随着你逐渐熟悉这些术语，它会变得更加清晰。|2935728|总之，类可以是数据类型(通常是*)。对象可以是变量(也可以是常量)。你在正确的轨道上！你越多地阅读或使用这些术语，区别就会变得越清晰。|2935729|*当我说“通常”时，我的意思是--通常在使用c%2B%2B的过程中，您会遇到的所有代码都会以某种方式使用类来表示数据。然而，在极少数情况下，有人会产生这样的想法:创建一个纯静态接口的类--没有数据。在他们辉煌的时刻，他们决定让构造器成为私有的，不允许实例化(使所谓的“单例”)。我从未将它们称为类型，也从未听说过任何人将它们称为类型。我很高兴在这一点上得到纠正，但就目前而言，这就是我的立场。|2935730|entityMap^0|13|3|29|4|3N|5|0|U|2|0|L|F|1P|Q|0|1D|5|1J|6|0|0|0^^$0|@$1|2|3|4|5|6|7|S|8|@$9|T|A|U|B|C]|$9|V|A|W|B|C]|$9|X|A|Y|B|D]]|E|@]|F|$]]|$1|G|3|H|5|6|7|Z|8|@$9|10|A|11|B|D]]|E|@]|F|$]]|$1|I|3|J|5|6|7|12|8|@$9|13|A|14|B|C]|$9|15|A|16|B|C]]|E|@]|F|$]]|$1|K|3|L|5|6|7|17|8|@$9|18|A|19|B|C]|$9|1A|A|1B|B|C]]|E|@]|F|$]]|$1|M|3|N|5|6|7|1C|8|@]|E|@]|F|$]]|$1|O|3|P|5|6|7|1D|8|@]|E|@]|F|$]]|$1|Q|3|-4|5|6|7|1E|8|@]|E|@]|F|$]]]|R|$]]

A data type is way of strongly indicating the way some data is used (in strongly-typed languages like c++). For example, the <code>int</code> datatype lets you know that you can perform actions traditionally associated with integer (whole) numbers. When something has the <code>char</code> data type, that lets you know that it can be used like a character (say, a letter of the alphabet). These two are examples of basic data types - built into the language.

A class is (usually*) a way of assembling some data, and giving it a unique interface to access and modify that data. The same way that you can add or subtract integers, or divide floating point numbers (without truncation), the functions you put in your class determine how it is used by your program. Similarly, classes created by others provide an interface so that you can use objects of those classes just like you would use integers.

Variables are the individual instances of some data type. If you have some <code>int number = 0;</code>, that is a variable. This stands in contrast to "constants", i.e., unmodifiable symbols like <code>const double pi = 3.14159;</code>.

The word "objects" can be considered ambiguous - most of the time, when people use the word "objects", they mean "instances of some <code>class</code> or <code>struct</code>". Sometimes though, it is used to refer to classes. This can be confusing, but will become more clear as you become comfortable with the terms.

In summary, classes can be datatypes (and usually are*). Objects can be variables (or constants, for that matter). You're on the right track! The more you read about or use these terms, the clearer the distinction will become.

*When I say "usually," what I mean is this - normally in the course of using c++, all of the code you will come across will use classes to represent data, in some way or another. However, on a rare occasion, someone gets into their head the idea of making a class that is pure static interface - no data. In their moment of brilliance, they decide to make the constructors private, disallowing instantiation (making what is called a "singleton"). I have never referred to these as types, or heard anyone else refer to them as types. I'm happy to be corrected on this, but for now, that's where I stand.

blocks|key|2935523|text|是的，您可以将类视为数据类型，也可以将类的实例视为变量。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|2935524|但是一个类可以不仅仅是一个数据类型--它支持绑定方法和数据。|2935525|如果您试图理解面向对象的设计和非面向对象的设计之间的区别，那么区分简单数据和属于类的数据是很有用的。在C中，数据是惰性的。单个变量或结构只是信息的容器。您可以将函数与该数据相关联，也可以采用约定来处理该数据，但是这种关联和约定必须由语言之外的某种约定强制执行。在像C%2B%2B这样的面向对象语言中，方法可以是对象的一部分。可以在对象、方法和字段级别定义数据访问。支持将继承作为一种语言功能。|2935526|深入了解技术细节：|2935527|类大致上与数据类型同义。变量大致与object同义。类是事物的抽象表示。它是一种描述，而不是事物本身。正如其他人所说，术语对象可以是模棱两可的-指的是一个类或该类的实例。更准确地说，一个对象(或类)的实例是一个变量。|2935528|entityMap^0|0|0|0|0|0^^$0|@$1|2|3|4|5|6|7|L|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|M|8|@]|9|@]|A|$]]|$1|D|3|E|5|6|7|N|8|@]|9|@]|A|$]]|$1|F|3|G|5|6|7|O|8|@]|9|@]|A|$]]|$1|H|3|I|5|6|7|P|8|@]|9|@]|A|$]]|$1|J|3|-4|5|6|7|Q|8|@]|9|@]|A|$]]]|K|$]]

Yes, you can consider a class to be a datatype, you can also consider an instance of a class to be a variable.

But a class can be more than a datatype - it supports bundling methods along with data.

If you are trying to understand the difference between object-oriented design and design that is not object-oriented, then it is useful to distinguish between simple data and data that is part of a class. In C, data is inert. An individual variable or a structure is simply a receptacle for information. You can associate functions with that data, and you can adopt conventions for dealing with that data, but the association and conventions must be imposed by some agreement beyond the language. In an object-oriented language like C++, methods can be part of objects. Data access can be defined at the object, method, and field level. Inheritance is supported as a language feature.

Getting into the technical details:

Class is roughly synonymous with datatype. Variable is roughly synonymous with object. A class is an abstract representation of a thing. It is a description rather than the thing itself. As others have said, the term object can be ambiguous - referring to either a class or instances of that class. It is more precise to say that an instance of an object (or class) is a variable.

blocks|key|697338|text|类和数据类型是一回事。把它们想象成房子的蓝图。物体就是根据这些蓝图建造的房子。变量是一个地址标签，它指向根据蓝图建造的房子。指针与变量相同，它只是一种定位已经建造的特定房屋的方法，因此它可以修改。|type|unstyled|depth|inlineStyleRanges|entityRanges|data|697339|希望这能有所帮助。|697340|entityMap^0|0|0^^$0|@$1|2|3|4|5|6|7|F|8|@]|9|@]|A|$]]|$1|B|3|C|5|6|7|G|8|@]|9|@]|A|$]]|$1|D|3|-4|5|6|7|H|8|@]|9|@]|A|$]]]|E|$]]

A class and data type are the same thing. Think of them as blueprints for a house. An object is a house constructed based on those blueprints. A variable is an address label that points to the house that was made from the blueprints. A pointer is the same as a variable, and it's just a way to locate a specific house that's been built, so it can be modified.

Hope this helps.

I'm having some trouble keeping apart the terms class, object, variable and datatype.

can a class be considered as a datatype?
can an object be considered as a variable?

Also, what's the technical difference?

Can an object be considered as a variable?

翻译质量差，导致语言生硬或混乱。

没有提供实际的解决方法或示例。

解答不清晰，无法理解或解决问题。

页面排版不美观，阅读体验差。

文章

问答

视频

学习中心

腾讯云实验室

直播

竞赛

腾讯云代码分析专区

腾讯iOA零信任安全管理系统专区

腾讯云架构师技术同盟交流圈

腾讯云数据库专区

腾讯云顾问专区

腾讯云原生专区

腾讯混元专区

腾讯云TCE专区

腾讯云Lighthouse专区

腾讯云HAI专区

腾讯云Edgeone专区

腾讯云存储专区

腾讯云智能专区

腾讯轻联专区 

腾讯云开发专区

TAPD专区

腾讯轻量云游戏服专区

腾讯云最具价值专家

腾讯云架构师技术同盟

腾讯云创作之星

腾讯云开发者先锋 

腾讯云代码助手

CODING DevOps

Cloud Studio

SDK中心

API中心

命令行工具

我在区分类、对象、变量和数据类型等术语时遇到了一些麻烦。类可以被认为是一种数据类型吗？一个对象可以被视为一个变量吗？另外，技术上的区别是什么？

问一个对象可以被视为一个变量吗？
EN

回答 6

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问一个对象可以被视为一个变量吗？EN

回答 6

Stack Overflow用户

Stack Overflow用户

Stack Overflow用户

社区

活动

圈层

关于

腾讯云开发者

热门产品

热门推荐

更多推荐

问一个对象可以被视为一个变量吗？
EN