javascript - 字符串替换某些匹配组，而不是整个匹配

Question

在 js 中，我想用一些文本替换字符串中的换行符，但前提是\n 前面有一个点和可选的空格。示例文本:

First sentence comes
split in two lines.

This would be a new sentence.

And the end

应该变成

"First sentence comes split in two lines.<br>This would be a new sentence.<br>And the end"

使用正则表达式:

text = text.replace(/\.\s(*\n)/g, "<br>");

替换整个匹配项，从而吃掉点，据我所知，RegEx.repace 不提供仅替换匹配组的方法。

实现该目标的最简单方法是什么？

Answer 1

您可以捕获组中的文字点，然后是换行符，后跟 0+ 个空白字符。

在替换使用组 1 后跟一个中断:$1<br>

\s*(\.)?\n\s*

Regex demo

const regex = /\s*(\.)?\n\s*/gm;
const str = `First sentence comes   
split in two lines.

This would be a new sentence.

And the end`;
const subst = `$1<br>`;
const result = str.replace(regex, subst);

console.log(result);

如果要删除第一个<br>同样，您也可以选择分两步完成:

const str = `First sentence comes   
split in two lines.

This would be a new sentence.

And the end`;
const result = str.replace(/\s*(\.)\s*/g, "$1<br>").replace(/\s*\n+\s*/g, " ");
console.log(result);