Re: Pattern etc to reduce duplicated validation?

David Lidstone wrote:

Hi All I seem to be writing a lot of this: //======== SCRIPT ========= $var = $_POST['var']; // validate $var $foo = new foo; $foo->setBar($var); //======== CLASS ========== class foo {

    public function setBar($var) {
        // validate $var
    }

} As you can see, the "issue" is that I am validating the input in my script, and then again in my class... surely unwanted duplication!? Obviously (I think!), I need to be validating at the level of my class, so does anyone have a pattern / strategy to help ease the pain... a way of using the validation in the class to validate the script and return meaningful errors to the user?? Throwing errors and forcing the script to catch them perhaps? I have tried a few validation classes etc and they have not really addressed this issue. Perhaps I should just live with it and get on with it! :) Many thanks for your help, David

Well, you could try looking at using exceptions: //==== CLASS ==== class foo {

    public function setBar($var)
    {
        if ( var_is_NOT_a_valid_value_for_bar )
        {
            throw new Exception('Invalid value for bar in class foo');
        }
    }

} // ===== Script ===== $var = $_POST['var']; $foo = new foo(); try {

    $foo->setBar($var);

} catch (Exception $e) {

    echo 'An error occurred: ',$e->getMessage(),"\n";

} Take a look at http://www.php.net/manual/en/language.exceptions.php -- Peter Ford phone: 01580 893333 Developer fax: 01580 893399 Justcroft International Ltd., Staplehurst, Kent