js 正则

[GenweiWu]

资料

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/RegExp

[GenweiWu]

下面这些怎么实现？

1、string.repalceAll ?

"/aa/bb/cc".replace(new RegExp("/[^/]+","gm"),"")
""

2、string.replaceFirst ?

"/aa/bb/cc".replace(new RegExp("/[^/]+","m"),"")
"/bb/cc"
"/11/22/33".replace(new RegExp("/[^/]+","m"),"")
"/22/33"

replace默认匹配第一个，g表示匹配所有，m表示进行多行匹配

[GenweiWu]

匹配和捕获

//1
'/a/b/c'.match('/[^/]+/[^/]+/[^/]+')
//2
'/a/b/c'.match('(/[^/]+)(/[^/]+)(/[^/]+)')
//3
'/a/b/c'.match('(?<group1>/[^/]+)(?<group2>/[^/]+)(?<group3>/[^/]+)')

理解

1. 0,1,2可以理解成group0，group1，group2
2. 增加()就会增加子group匹配
3. 使用?<name>来得到命名的group匹配

参考

• https://developer.mozilla.org/zh-CN/docs/Web/JavaScript/Reference/Global_Objects/String/match
• https://javascript.info/regexp-groups