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【进站必读】宝可饭堂社区全局规定v1.10

关于坚决维护同人创作社群秩序与共识的公告

信息: <blockquote data-quote="TAAAAAAA" data-source="post: 2355" data-attributes="member: 2783">Writing your own classes 新建一个类You’re not limited to just the existing, internal classes like String, Array and the like. You can also create your own. A class has a name, and this name is a constant - this means that it starts with an uppercase letter and cannot contain any special characters or operators like !@#$%^&*() (and a lot more, probably).除了本来就有的内置的类外，我们也可以新建类。一个类需要有一个名字，类的名字是一个常量，也就是说，类的名字以大写字母开头，并且，类的名字不能包含有特殊字符，同时，类是唯一的，不存在两个名字相同的类。To create or define a class, you use the class keyword, followed by the name. Just like for, def, and if, class has to be closed with end. In the example below we’ll create a class named CustomClass with nothing in it:你可以使用class关键词新创建一个类，就跟def定义新方法一样，定义新类你也需要在结尾加上end。我们来看下面这个例子：Now, if you type CustomClass in your code, you’re referring to this newly created class. If you do this before the class is actually defined, it won’t exist yet, and using it will cause errors. But now you can also use this in methods like something.is_a?(CustomClass), or something.class == CustomClass.现在，你可以使用is_a?(CustomClass)来检查一个对象是否是CustomClass类了。We now have a class, but we don’t have any instances of it yet. To initialize an instance of CustomClass, you write CustomClass.new. This returns an object, which is an instance of CustomClass. You should store this in a variable somewhere so you can use it again later.现在，我们有了一个类，但是我们还没有这个类的任何实例。要创建一个这个类的实例，我们需要这样写CustomClass.new，也就是说，我们对这个类调用new（新的）方法，这样就会创建一个这个类的实例。创建了实例之后，我们应该把它和变量关联起来，这样我们就能随时使用这个实例了。When you do [1,2,3].size #=> 3, you’re calling the instance method called size on an instance of an array (hence it’s called instance method, duh). You can very easily add similar instance methods to your class by simply defining a method like you normally would.目前，我们的新类中还并没有任何的实例方法，那我们就根据我们之前学过的内容，新建一个实例方法吧，请看下面的例子：To test this out, we create an instance of the class with CustomClass.new, and then call .say_hello on it:我们来看下面的这个例子：This might be a bit confusing when you’re used to the special 1..6, “hello”, [1,2,3] formats and the like to create an instance of a class. These are actually just very special ways to create an instance of those classes - normally, for any class, you would use <ClassName>.new. (And no, there’s no way to make one of these kind of formats yourself, unfortunately. You’re stuck with .new).</blockquote>