php regular expression example

Regular expression(regular expression) describes a stringmatching pattern (pattern), which can be used to check whether a string contains a certain substring and match the Substring replacement or removing a substring that meets a certain condition from a certain string, etc.

Regular expressions are text patterns composed of ordinary characters (such as the characters a through z) and special characters (called "metacharacters"). A pattern describes one or more strings to match when searching for text. A regular expression acts as a template that matches a character pattern with a searched string.

Example

<?php
$str = <<< EOT
        <a href="www/app/a/2QRN7v" rel="external nofollow" >
          <p class="phonebg">
            <img src="http://www/template9/yunqingjian/jianjie/68.jpg" >
            <p class="phoneclick"></p>
            <p>幸福领地</p>
          </p>
        </a>
        <a href="www/app/a/uqARNv" rel="external nofollow" >
          <p class="phonebg">
            <img src="http://www/template9/yunqingjian/jianjie/69.jpg" >
            <p class="phoneclick"></p>
            <p>一世情长</p>
          </p>
        </a>
EOT;
if(preg_match_all(&#39;%<p.*?>(.*?)</p>%si&#39;, $str, $matches)) {
  $arr[0][] = $matches[1];
}
if(preg_match_all(&#39;/src="([^<]*)" >/i&#39;, $str, $matches)) {
  $arr[1][] = $matches[1];
}
print_r($arr);
exit;
?>

The running results are as follows:

Array
(
  [0] => Array
    (
      [0] => Array
        (
          [0] => 幸福领地
          [1] => 一世情长
        )
    )
  [1] => Array
    (
      [0] => Array
        (
          [0] => http://www/template9/yunqingjian/jianjie/68.jpg
          [1] => http://www/template9/yunqingjian/jianjie/69.jpg
        )
    )
)

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