PHP preg_match 查找多次出现

Question

在 PHP 中使用 preg_match 查找同一字符串多次出现的正则表达式的正确语法是什么？

例如，查找以下字符串是否在以下段落中出现两次:

$string = "/brown fox jumped [0-9]/";

$paragraph = "The brown fox jumped 1 time over the fence. The green fox did not. Then the brown fox jumped 2 times over the fence"

if (preg_match($string, $paragraph)) {
echo "match found";
}else {
echo "match NOT found";
}

Answer 1

您想使用 preg_match_all() .这是它在您的代码中的样子。实际函数返回找到的项目数，但 $matches 数组将保存结果:

<?php
$string = "/brown fox jumped [0-9]/";

$paragraph = "The brown fox jumped 1 time over the fence. The green fox did not. Then the brown fox jumped 2 times over the fence";

if (preg_match_all($string, $paragraph, $matches)) {
  echo count($matches[0]) . " matches found";
}else {
  echo "match NOT found";
}
?>

将输出:

2 matches found