class selector meaning in English

称为类选择符

With the class selector you can define different styles for the same type of html element
用选择器类你可以将同一类型的html元素定义出不同的样式。
It ' s especially important that you familiarize yourself with class selectors , as many of the examples below will use them
最重要的一点是，你需要熟悉分类器，因为下面我们会用到。
A coherent style of verifications makes the implementations smaller and more robust : selectors verify the object , its class , and the existence of a method ; super ? class selectors should additionally verify the new class argument ; a dynamically linked method is only called through a selector , i . e . , it need not verify its object
检验方法协调一致的风格使得（软件的）实现更小巧而坚固：选择器检验对象、对象的类以及方法的存在；基类选择器应当检验新的类参数；动态连接方法总是通过选择器调用的，也即它不需要检验其所属对象。