title: How to use strpos to determine if a string exists in input string?
body: <pre><code>$filename = 'my_upgrade(1).zip';
  $match = 'my_upgrade';
  
  if(!strpos($filename, $match))
      {
      die();
      }
  else 
     {
     //proceed
     }
  </code></pre>
  
  <p>In the code above, I'm trying to die out of the script when the filename does not contain the text string "my_upgrade". However, in the example given, it should not die since "<strong>my_upgrade(1).zip</strong>" contains the string "<strong>my_upgrade</strong>". </p>
  
  <p>What am I missing?</p>