NAME

WWW::FieldValidator

SYNOPSIS

WWW::FieldValidator - Used by WWW::Form, provides simple yet robust validation of user entered input

DESCRIPTION

This module is used by WWW::Form to perform various validations on input. This document covers using the WWW::FieldValidator module as part of a Form object. In this case, the only thing you need to know how to do is to instantiate WWW::FieldValidators properly. All the validation is handled internally by WWW::Form.

Function Reference

new($validatorType, $errorFeedback, [$minLength, $maxLength, $regex], [$isOptional]);

Creates a FieldValidator object.  $validatorType is used to determine what type
of validation will be performed on the input.  The following validator types are
supported (Note these are constants, the $validatorType param needs to be one of
the following values):

WWW::FieldValidator::WELL_FORMED_EMAIL # input must conform to /^[\w\-\.\+]+@(\w+)(\.([\w\-]+))+$/
WWW::FieldValidator::MIN_STR_LENGTH    # input must be >= a specified string length
WWW::FieldValidator::MAX_STR_LENGTH    # input must be <= a specified string length
WWW::FieldValidator::REGEX_MATCH       # input must match a user defined regex
WWW::FieldValidator::USER_DEFINED_SUB  # input must pass a user defined subroutine's validation

Examples:

# create a validator that checks to see if input is a well formed email address
WWW::FieldValidator->new(WWW::FieldValidator::WELL_FORMED_EMAIL,
                         'Please make sure you enter a well formed email address');

# creates a validator that checks to see if input is 
# well formed only if input is not null (or numm string)
WWW::FieldValidator->new(WWW::FieldValidator::WELL_FORMED_EMAIL,
                         'Please make sure you enter a well formed email address',
                         $isOptional = 1);

# creates a validator that checks to see if the input is at least min length
WWW::FieldValidator->new(WWW::FieldValidator::MIN_STR_LENGTH,
                         'Please make sure you enter something at least 10 characters long',
                         10);

# creates a validator that checks to see if the input is at least min length
# only if input is not null or null string
WWW::FieldValidator->new(WWW::FieldValidator::MIN_STR_LENGTH,
                         'Please make sure you enter something at least 10 characters long',
                         10,
                         1);

# creates a validator that checks to see if the input is less than max length
WWW::FieldValidator->new(WWW::FieldValidator::MAX_STR_LENGTH,
                         'Please make sure you enter something less than or equal to 5 characters',
                         5);

# creates a validator that checks to see if the input is less than max length
# only if input is not null or null string
WWW::FieldValidator->new(WWW::FieldValidator::MAX_STR_LENGTH,
                         'Please make sure you enter something less than or equal to 5 characters',
                         5,
                         1);

# creates a validator that checks to see if the input matches the specified regex
WWW::FieldValidator->new(WWW::FieldValidator::REGEX_MATCH,
                         'Please make sure you enter a number',
                         ^\d+$|^\d+\.\d*$|^\d*\.\d+$');

# creates a validator that checks to see if the input matches the specified regex
# only if input is not null or null string
WWW::FieldValidator->new(WWW::FieldValidator::REGEX_MATCH,
                         'If you are going to enter anything please make sure you enter a number',
                         ^\d+$|^\d+\.\d*$|^\d*\.\d+$',
                         1);


# creates a validator that checks to see if the input is good according to sub ref
WWW::FieldValidator->new(WWW::FieldValidator::USER_DEFINED_SUB,
                         'The name you entered already exists',
                         \&is_name_unique);

# creates a validator that checks to see if the input is good according to sub ref
# only if input is not null or null string
WWW::FieldValidator->new(WWW::FieldValidator::USER_DEFINED_SUB,
                         'If you are going to enter a name, you must enter one that does not already exist',
                         \&is_name_unique,
                         1);

# if you use the validator type: USER_DEFINED_SUB, your subroutine will have access to
# the value of the form input that your validator is assigned to
Example:
sub is_name_unique {
    # gets passed in to this sub for you by way of Form module
    my $name = shift;

    if ($names->{$name}) {
        return 0; # name already exists, input is invalid
    } else {
        return 1;
    }
}

SEE ALSO

WWW::Form

AUTHOR

Ben Schmaus

If you find this module useful or have any suggestions or comments please send me an email at perlmods@benschmaus.com.

BUGS

Don't know of any, but let me know if you find any.

Send email to perlmods@benschmaus.com

COPYRIGHT

Copyright 2003, Ben Schmaus. All Rights Reserved.

This program is free software. You may copy or redistribute it under the same terms as Perl itself. If you find this module useful, please let me know.