Question

如果我在比赛中寻找锚词，例如句子中的单词颜色如果该句子中有颜色但在OR之后匹配正常：

红色
红色

我能用一两个正则表达式做这个吗我需要两个：

(Color (Red|Blue|Orange))

https://regex101.com/r/iT4nN6/1

((Red|Blue|Orange) Color)

https://regex101.com/r/iT4nN6/2

Answer 1

你可以做一个正则表达式：

如果事情变得更复杂，那么维护起来会更困难;你需要在两个地方更新颜色列表。根据您的具体情况，单独执行这两个组件可能更容易，只在另一个组件的结果中查找一个组件。

Answer 2

在PHP PCRE正则表达式语法中，您可以利用(?J)修饰符，该修饰符允许对不同的捕获组使用相同的名称：

(?J)(?<colorword>Color)\h+(?<color>Reddish|Red|Blue|Orange)|(?<color>Reddish|Red|Blue|Orange)\h+(?<colorword>Color)

请参阅the regex demo

PHP demo：

$clrw = '(?<colorword>Color)';
$clr = '(?<color>Reddish|Red|Blue|Orange)';
$re = '~(?J)' . $clrw . '\h+' . $clrw . '|' . $clr . '\h+' . $clrw . '~i'; 
$str = " I WANT TO EXTRACT CAPTURING GROUP 2 AS COLOR AND I DO:\nand  love the Color Red\n \nI WANT TO EXTRACT CAPTURING GROUP 2 AS COLOR BUT I DONT AS I HAVE TO REVERSE THE GROUPS TI ((Red|Blue|Orange) Color):\nit had a reddish color\n\nI DON'T WANT ANYTHING BECAUSE IT ISN'T PRECEDED OR FOLLOWED BY THE WORD COLOR\nit is a red dawn \nI took the red eye home\nit was the color red"; 
preg_match_all($re, $str, $matches, PREG_SET_ORDER);
for ($i = 0; $i < count($matches); $i++) {
    echo $matches[$i]["color"] . ": " . $matches[$i]["colorword"] . PHP_EOL;
}

结果：

Red: Color
reddish: color
red: color

在一个正则表达式之前或之后模式匹配的正则表达式？

2 个答案: