www.worldentity.com

1. Email validation
$pattern = "/^[a-zA-Z0-9._-]+@[a-zA-Z0-9-]+\.[a-zA-Z.]{2,5}$/";
$email = "jim@demo.com";
if (preg_match($pattern,$email)){
echo "Match";
}
else{
echo "Not match";
}
2. Url validation
$pattern = "/]*)[\"\']?[^>]*>(.*?)<\/a>/i";
$url = "http://www.worldentity.com/";
if (preg_match($pattern,$url)){
echo "Match";
}
else{
echo "Not match";
}

3. Address: ZIP code (US)
$pattern='\b[0-9]{5}(?:-[0-9]{4})?\b';
4. Credit card: All major cards
$pattern='^(?:4[0-9]{12}(?:[0-9]{3})?|5[1-5][0-9]{14}|6011[0-9]{12}|3(?:0[0-5]|[68][0-9])[0-9]{11}|3[47][0-9]{13})$';

5. Credit card: American Express
$pattern='^3[47][0-9]{13}$';

6. Credit card: Diners Club
$pattern='^3(?:0[0-5]|[68][0-9])[0-9]{11}$';

7. Credit card: Discover
$pattern='^6011[0-9]{12}$';

8. Credit card: MasterCard
$pattern='^5[1-5][0-9]{14}$';

9. Credit card: Visa
$pattern='^4[0-9]{12}(?:[0-9]{3})?$';

10. Credit card: remove non-digits
$pattern='/[^0-9]+/';
11. Matches any opening or closing HTML tag, without its contents.
$pattern=']*>';
12. Change the date format from "yyyy-mm-dd" to "mm/dd/yyy"
preg_replace("/(\d+)-(\d+)-(\d+)/", "$2/$3/$1", "2007-01-25");