字符类中的斜杠“ /”有什么特殊含义

Question

In docs I can't find anything. But for pattern work properly in character class I need to escape / like this "\\/". Why I need do so? Sorry for my english. I'm using PCRE and preg_match function. Oh my God, sorry all and thanks for help. I'm using / delimiters.

Answer 1

尽管/在正则表达式本身的上下文中可能没有任何意义，但取决于编程语言， /可能用于封装正则表达式字符串，因此需要转义。

Answer 2

you don't have to escape / in [...]

[/] should work.

and in regex, / doesn't have special meaning. it is literal slash.

Answer 3

It isn't the regular expression itself but how it is getting parsed by the language. For example in Ruby:

 "/".match(/[/]/)

is a syntax error but:

 "/".match(/[\/]/)

will work.

Answer 4

I know only one case when you should do it if you use regular expression like this one:

/something here / something here / . I mean that / is start and end bound of your reg. exr.