PHP regular matching for strings

This article mainly introduces PHP's regular matching of strings. Interested friends can refer to it. I hope it will be helpful to everyone.

The specific implementation method is as follows:

/** * is_external_link 检测字符串是否包含外链 * @param string $text 文字 * @param string $host 域名 * @return boolean false 有外链 true 无外链 * / function all_external_link($text = '', $host = '') { if (empty($host)) $host = $_SERVER['HTTP_HOST']; $reg = '/http(?:s?):\/\/((?:[A-za-z0-9-]+\.)+[A-za-z]{2,4})/'; preg_match_all($reg, $text, $data); $math = $data[1]; foreach ($math as $value) { if($value != $host) return false; } return true; }

Summary: The above is the entire content of this article, I hope it can be helpful to everyone’s study .

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