title: How do i extract some data in string? using PHP
body: <p>I have a string of URL format.</p>
  
  <p>It is this.
  "<a href="http://test.com/foo/bar/detail.php?key=KEY&amp;other=x" rel="nofollow noreferrer">http://test.com/foo/bar/detail.php?key=KEY&amp;other=x</a>"</p>
  
  <p>What I need is to extract "KEY" from URL.</p>
  
  <p>It is similar this.<br/></p>
  
  <pre><code>$foo = $_GET['key'];
  </code></pre>
  
  <p>But what I have is a string of URL format.<br/>
  How do i extract KEY this string?</p>