preg_match name of input field inside form

问题

Sorry, i spent like 2 hours trying to preg_match this form

<form class="form-search" method="post" action="/index.php">
  <div class="form-group">
    <input id="address_box" type="text" class="form-control" name="x" value="" onfocus="this.select()" />
  </div>
<span class="btn btn-s btn-caps"><input type="submit" value="start" /></span>
</form>

To:

Preg_match:

START = <form

WHERE action CONTAIN /index.php
EX: action="/index.php" or action="http://whatever.com/index.php"

FIND name="[A-Za-z]{1}"

END = </form>

Then Output the [A-Za-z]{1} Match (Should get x)

How can i do it correctly please?

Thanks.

回答1:

$pat = /\/index.php\">.*?form-control\".*(?<=name=\")([A-Za-z]{1})(?=\")/s

$sub = '<form class="form-search" method="post" action="/index.php">
  <div class="form-group">
    <input id="address_box" type="text" class="form-control" name="x" value="" onfocus="this.select()" />
  </div>
<span class="btn btn-s btn-caps"><input type="submit" value="start" /></span>
</form>';

preg_match($pat,$sub,$match);


to echo mateched use echo $match[1];

回答2:

Ok, this regex should do the job:

$regex = '/<form.*(?<=action=\")?\/index.php\">.*(?<=name=\")([A-Za-z]{1})(?=\").*?<\/form>/s';

来源：https://stackoverflow.com/questions/29052172/preg-match-name-of-input-field-inside-form