后代选择器用双斜线 // 表示。

A descendant selector is represented by a double-slash: //.

youdao

但是，方括号中谓词前的单斜线或双斜线（/ 或 //）没有上下文，所以引用到文档的根。

However, a slash or a double slash ( / or // ) at the front of a predicate in square brackets does not have a context and therefore refers to the root of the document.

youdao

但是，方括号中谓词前的单斜线或双斜线（/ 或 //）没有上下文，所以引用到文档的根。

However, a slash or a double slash ( / or // ) at the front of a predicate in square brackets does not have a context and therefore refers to the root of the document.

youdao