Snip!t from collection of Alan Dix

<tr><td class="namehead">Regular Expression Tester</td> </tr> <tr> <td class="info"><img src="images/spacer.gif" border="0" height="5" width="1"></td> </tr> <tr> <td class="info">Anytime I use Regular Expressions, I find myself doing a bit of trial-and-error until I get the right pattern. So, I whipped this up to help...<p> Due to popular demand, I've added parenthesized substring support.</p></td> </tr> <tr> <td class="info"><img src="images/spacer.gif" border="0" height="15" width="1"></td> </tr> <tr> <td class="info"><form action="/regex.php" method="post"><table border="0"><tbody><tr><td class="info">Pattern:</td><td><input name="pattern" value="/^(.+)@([^\(\);:,&lt;&gt;]+\.[a-zA-Z]{2,4})/" class="info" size="40" type="test"></td></tr><tr><td class="info">Haystack:</td><td><input name="haystack" value="joE@free.com is valid email." class="info" size="40" type="test"></td></tr><tr><td class="info" colspan="2"><input name="rtype" value="1" checked="checked" type="radio"> preg (Perl) <input name="rtype" value="2" type="radio"> ereg (POSIX)</td></tr><tr><td class="info" colspan="2" align="right"><input name="submit" value="Submit" class="info" type="submit"></td></tr></tbody></table></form></td> </tr> <tr> <td class="info"><img src="images/spacer.gif" border="0" height="15" width="1"></td></tr>