help on this please

[~n[EO]n~]

hi anybody knows how to validate form field for numbers, text etc... just one line example will do

 

if (empty($_REQUEST['co_telephone']))
	$app->error('Please enter Telephone');
// i have validated like this but i only want to accept numbers 9 characters only, it only checks if it is blank or not

 

any help will be most welcome...

[jscix]

if (empty($_REQUEST['co_telephone']) || !(is_numeric($_REQUEST['co_telephone'])) || strlen($_REQUEST['co_telephone']) !== 9)

    {

          $app->error('Please enter Telephone');

    }