<?
<p>$x = array(&quot;20040301&quot;, &quot;20041301&quot;, &quot;20040341&quot;, &quot;21040301&quot;, &quot;18040301&quot;, &quot;19040301&quot;);</p>
<p>$y = 0;</p>
<p>while ($y &lt;= count($x)) {<br>
  echo $x[$y];<br>
  if (!ereg(&quot;\d{8}&quot;, $x[$y])) echo &quot; is BAD&lt;br&gt;&quot;; // &quot;^(19|20)\d{2}(0|1)\d(0-3)\d$&quot;<br>
  else echo &quot; is GOOD&lt;br&gt;&quot;;<br>
  $y++;<br>
  }<br>
  ?&gt;</p>
<p>&nbsp;</p>
<p>&nbsp;</p>
<p>&nbsp;</p>
<?
echo time();
echo "<br><br><br>";
$x = array("20040301", "20041301", "20040341", "21040301","20042301", "18040301", "19040301", "200403012", "2004030", "20040230", "20040229");

$y = 0;

while ($y < count($x)) {

	switch ($x[$y]) {
	case !preg_match("/^(19|20)\d{2}(0|1)\d{1}[0-3]\d{1}$/", $x[$y]): 
		echo $x[$y]." is BAD<br>";
		break;
	case strtotime($x[$y])=== -1: 
		echo $x[$y]." (".date("Y-m-d", strtotime($x[$y])).") is WRONG<br>";// "^(19|20)\d{2}(0|1)\d(0-3)\d$"
		break;
	default:
		echo $x[$y]." is GOOD<br>";
	}
$y++;
echo "<br>";
}
?>