用grep查找两个字符之间的字符串

本文介绍了用grep查找两个字符之间的字符串的处理方法，对大家解决问题具有一定的参考价值，需要的朋友们下面随着小编来一起学习吧！ 问题描述

我在此 answer 正则表达式中找到了两个字符之间的字符串.就我而言，我想找到‘和’之间的所有模式.这是正则表达式:

I have found on this answer the regex to find a string between two characters. In my case I want to find every pattern between ‘ and ’. Here's the regex :

(?<=‘)(.*?)(?=’)

实际上，当我在 regex101/上尝试时，它可以工作.

Indeed, it works when I try it on regex101/.

我要在 grep 中使用它，但是它不起作用:

The thing is I want to use it with grep but it doesn't work :

grep -E '(?<=‘)(.*?)(?=’)' file

有什么遗漏吗?

推荐答案

这些都是积极的前瞻性，并且在声明后面.您需要使用PCRE(Perl兼容正则表达式)启用它，也许最好使用GNU grep 中的 -o 选项获得匹配的部分:

Those are positive look-ahead and look behind assertions. You need to enable it using PCRE(Perl Compatible Regex) and perhaps its better to get only matching part using -o option in GNU grep:

grep -oP '(?<=‘)(.*?)(?=’)' file