PHP：如何获取 preg_match_all 的字符串索引？

Question

假设我有两个正则表达式：

/eat (apple|pear)/
/I like/

和文本

"I like to eat apples on a rainy day, but on sunny days, I like to eat pears."

我的目的是用preg_match获取以下索引：

match: 0,5 (I like)
match: 10,19 (eat apples)
match: 57,62 (I like)
match: 67,75 (eat pears)

有没有办法使用preg_match_all获取这些索引，而不必每次都循环遍历文本？

编辑：解决方案 PREG_OFFSET_CAPTURE！

- atp

Answer 1

您可以尝试在preg_match()中使用PREG_OFFSET_CAPTURE标志:

$subject="I like to eat apples on a rainy day, but on sunny days, I like to eat pears.";
$pattern = '/eat (apple|pear)/';
preg_match($pattern, $subject, $matches, PREG_OFFSET_CAPTURE );
print_r($matches);

输出

$ php test.php
Array
(
    [0] => Array
        (
            [0] => eat apple
            [1] => 10
        )

    [1] => Array
        (
            [0] => apple
            [1] => 14
        )

)

- ghostdog74

---

同样适用于preg_match_all() :D - bbeckford

Answer 2

请记住，如果您使用preg_match，并且未匹配到组，则不会返回数组，而是返回空字符串。您可以使用T-Regx并使用更简洁的API：

$o = pattern('eat (apple|pear)')->match($text)->offsets()->all();
$o // [10, 14]

或者如果你想要一些更高级的匹配

pattern('eat (apple|pear)')
  ->match($text)
  ->iterate(function (Match $m) {
      $m->text();   // your fruit here
      $m->offset(); // your offset here
  });

- Danon