Online regular expression matching test

I’ve been learning regular expressions recently and I just happened to write an online php that matches regular expressions and share it with everyone~

<?php //正则表达式学习系统
if($_POST[&#39;text&#39;])
{
	$str=$_POST[&#39;text&#39;];//file_get_contents("a.dat");
	preg_match_all(&#39;/&#39;.$_POST[&#39;reg&#39;].&#39;/&#39;,$str,$s);
	print_r($s);
}
?>
<meta charset="utf-8">
<title>Reg learning</title>
<link rel="stylesheet" href="/assets/css/amazeui.min.css">
<div class="am-g">
  <div class=" col-md-8 col-sm-centered">
    <form class="am-form" action="#" method="post">
      <fieldset class="am-form-set">
        <input type="text" id="text" name="text" placeholder="text">
        <input type="text" id="reg" name="reg" placeholder="reg">
      </fieldset>
      <div><button type="submit" class="am-btn am-btn-primary am-btn-block">match!</button></div>
    </form>
  </div>
</div>

The above introduces the online regular expression matching test, including the relevant content. I hope it will be helpful to friends who are interested in PHP tutorials.