JavaScript正则分组的相关内容

文章 2022-09-14 来自：开发者社区

JS：RegExp正则命名分组

// 使用RegExp需要注意转义符 let re = new RegExp('(?<year>\\d{4})-(?<month>\\d{2})-(?<day>\\d{2})'); let match = re.exec('2021-12-14'); console.log(match); // 没有匹配到会返回null if(match){ let {y...

问答 2016-06-23 来自：开发者社区

代码功能是检测一个html元素中是否包含某个类，但是在使用正则的过程中我就是不理解为什么要加分组，分组的作用是什么，以及在这里是怎么去匹配的，如果没加分组会如何？我试过了，如果不加分组，匹配是不正确的。![screenshot](https://oss-cn-hangzhou.aliyuncs.com/yqfiles/71d1a2a7319e83040e7c171010de720ed7e953e....

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更新时间 2022-09-28 13:52:52

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