nmerriweather has asked for the wisdom of the Perl Monks concerning the following question:

I've written a custom form class to handle making & validating forms.

usage:
my $form = new FormObject( $ref2QuestionsHash, $ref2QuestionsOrderArra
+y );
$form->printForm;
$form->validate($ref2UserInput)

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i'm working out the validation of select boxes right now -- I want only the selectbox options to be valid.

Options are assigned to a selectbox using an array of value/text pairs as follows: 
'data' =>    [
            ['m','male'],
            ['f','female'],
        ],

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That would result in html of : _option value="m"_ male _/option_ -- and an f/female

Validating this, right now, happens as follows:
my $valid = 0;
for (my $i=0; $i<=$#{$question->{'data'}};$i++){
    if ( $answer eq ${$question->{'data'}}[$i][0] ) {
        $valid = 1;
        last;
    }
}

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So, my question is - anyone have a better idea? The only other option I considered was creating a hash of acceptable answers and checking existance -- but to accomplish that I'd either have to pre-compute the hash keys, which saves me looping at the expense of memory, OR i'd loop through it realtime to make the hash -- which this method does already without the added step of checking the hash

Replies are listed 'Best First'.
Re: web form processing - efficiency question
by blokhead (Monsignor) on May 07, 2004 at 00:26 UTC
    I'm not sure I understand your reservations about hashes, or what you mean by "precomputing hash keys" and extra memory.

    The only thing you lose by moving to a hash is the ordering of the keys, but you can get that back: 

    my $question = {
    descriptions => {
        m => "male",
        f => "female",
        o => "other"
    },
    choices => [ qw/m f o/ ]
}

    [download]
    Then to generate the HTML in the right order is not so bad (not that I'm a big fan of this -- you should be using a templating system anyway): 
    for my $choice ( @{ $question->{choices} } ) {
    my $text = $question->{descriptions}{$choice};
    print qq[<option value="$choice">$text</option>\n];
}

    [download]
    And validating choices becomes trivial: 
    $valid = exists $question->{descriptions}{$answer};

    [download]
    Anyway, having an array of arrays, with inner arrays having just 2 items, is a good sign that a hash (or certainly a relation matrix) might be in order.

    blokhead

[reply]
[d/l]
[select]
      I never thought of that approach -- i'm going to give that a shot.

      I severly disliked every templating system I came across in the past few weeks -- so I decided to build my own. The only part i questioned so far was html select fields.
[reply]
        did you also check out Template-Magic? its very simple to use and very flexible.

        for the form-data validation must of us use Data::FormValidator which is mature.
        ciao
        philipp
[reply]

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