Re: Re: speaking of control structures...

Tom Worster wrote:

On 5/6/09 4:02 PM, "Al" <news@ridersite.org> wrote:

Here's the way I handle validating user form inputs. Each function validates several things and throws an error with the message stating what's wrong. try

         {
             checkEmailAddr($userSubmitedDataArray[EMAIL_ADDR_FIELD]);
             checkPhoneDigits($userSubmitedDataArray[PHONE_NUM_FIELD],

'phone');

             checkNotes($userSubmitedDataArray, $sizesArray);
             if(!empty($userSubmitedDataArray[CELLPHONE_NUM_FIELD]))
             {

checkPhoneDigits($userSubmitedDataArray[CELLPHONE_NUM_FIELD], 'cell');

                 checkCellCarrier($userSubmitedDataArray['carrier']);
             }
         }

         catch (Exception $e)
         {
             $userErrorMsg = $e->getMessage(); //Message text in check

function

         }

A typical function looks like this: function checkEmailAddr($emailAddr) {

     if(empty($emailAddr))
     {
         throw new Exception("No email address provided");
     }

     if(!preg_match("%\w+@%", $emailAddr))
     {
         throw new Exception("Email address missing mailbox name.");
     }

     if(!filter_var($emailAddr, FILTER_VALIDATE_EMAIL))
     {
         throw new Exception("Email address error. Syntax is wrong. ");
     }
     $domain = substr(strchr($emailAddr, '@'), 1);
     if(!checkdnsrr($domain))
     {
         throw new Exception("Email address warning. Specified domain

\"$domain\" appears to be invalid. Check carefully.");

     }
     return true;

}

thanks for the example, Al. the combination of checker functions and exceptions (as far as i understand them, the exceptions chapter of the php manual is a little terse) so you can throw from inside the checker seems convenient.

Incidentally, the throw new exception doesn't have to be in a function. it can be simply in your code sequence. e.g., if($foo != 'boo') throw new Exception("foo is not equal to boo. "); try/catch is a God sent for me. I'm big on telling the user everything that is wrong with their entry and what to do about it. Prior to try/catch being available, I'd have to have to test the return for "true" or a message and then have logic to skip over the following checks to post a message for the user. Keep in mind, with this approach, it is most useful if you want to inform users about errors one at a time. If you want to get fancy, you can control the exception handler. See manual on this.