How to check if string value returned from text input is integer
<p>I have a form where users search for keywords.</p>

<p>I want to check if users submit a number (integer) instead of a keyword.</p>

<p>I use this:</p>

<pre><code>$keyword = $_REQUEST["keyword"];

if (is_int($keyword)) {
  echo 'true';
} else {
  echo 'false';
}
</code></pre>

<p>but it always returns false even when the value submitted is integer.</p>
