NYCPHP Meetup

[Dan Cech]

Jay,

As far as I know function definitions within conditional blocks are 
executed inline with the other code, thus the behaviour you describe 
would be correct as the function would not yet have been defined.

I could be way off though...

Dan

Jayesh Sheth wrote:
> Hello all,
> 
> I have come across commonly occuring QuickForm bug that might be due to 
> either a QuickForm bug or a Zend Engine bug (unless I am doing something 
> really stupid here.)
> 
> Okay, here's the gist of it:
> 
> If a QuickForm object is instantiated inside of a conditional check, the 
> callback processing function will not be run, UNLESS the callback 
> function is defined BEFORE the if "( $form->validate() )" check.
> 
> (The following examples are based on sample code from David Sklar's 
> "Essential PHP Tools" book.)
> For example, in the following case, the callback function will NOT be run:
> ---------------------------
> <?php
> /*
> praise_book() function is defined AFTER  'if ($form->validate())'
> The callback function will now NOT be run
> This is a PHP or QF bug
> */
> 
> define ("IS_TRUE", true);
> 
> if (IS_TRUE)
> {
> // Load the HTML_QuickForm module
> require 'HTML/QuickForm.php';
> 
> // Instantiate a new form
> $form = new HTML_QuickForm('book');
> // Add a text box
> $form->addElement('text','title','Book Title:');
> // Add a select box
> $subjects = array('Math','Ice Fishing','Anatomy');
> $form->addElement('select','subject','Subject(s): ',$subjects);
> // Add a submit button
> $form->addElement('submit','save','Save Book');
> 
> // Add a validation rule: title is required
> $form->addRule('title','Please Enter a Book Title','required');
> 
> $praise_book_called = false;
> 
> // Call the processing function if the submitted form
> // data is valid; otherwise, display the form
> if ( $form->validate() )
> {
>    $f = $form->process('praise_book');
>      if (! $f || ! $praise_book_called)
>    {
>        if ( ! $praise_book_called )
>        {
>        echo "<p> Error / PHP Bug: </p>";
>        echo "<pre>";
>        print_r($f);
>        echo "</pre>";
>        }
>        else
>        {
>           echo "<p>Other error.</p>";
>        }
>    }
> }
> else
> {
>      $form->display();
> }
> 
> // Define a function to process the form data
> function praise_book($v)
> {
>    global $subjects, $praise_book_called;
>    $praise_book_called = true;
>    // Entity-encode any special characters in $v['title']
>    $v['title'] = htmlentities($v['title']);
>    print "<i>$v[title]</i> is a great book about ";
>    print $subjects[$v['subject']] . '.';
>      return true;
> }
> 
> }
> else
> {
>    exit("<p>Error: An unknown error has occured. Exiting.</p>");
> }
> ?>
> ---------------------------
> The following error will be outputted (via print_r() )
> 
> ---------------------------
> Error / PHP Bug:
> 
> HTML_QuickForm_Error Object
> (
>    [error_message_prefix] => QuickForm Error:    [mode] => 1
>    [level] => 1024
>    [code] => -7
>    [message] => process callback does not exist
>    [userinfo] => Callback function does not exist in QuickForm::process()
>    [backtrace] => Array
>        (
>            [0] => Array
>                (
>                    [file] => 
> c:\apachefriends\xampp\php\pear\HTML\QuickForm.php
>                    [line] => 1818
>                    [function] => PEAR_Error
>                    [class] => HTML_QuickForm_Error
>                    [type] => ->
>                    [args] => Array
>                        (
>                            [0] => process callback does not exist
>                            [1] => -7
>                            [2] => 1
>                            [3] => 1024
>                            [4] => Callback function does not exist in 
> QuickForm::process()
>                        )
> 
>                )
> 
>            [SNIP ... more stuff in here. Please run the example to see 
> the entire output.]
> )
> 
> -------------------------
> Now, in the following case, if praise_book is defined before 'if 
> ($form->validate())', it will work as expected. Also, if the conditional 
> check "if (IS_TRUE)" is removed, it will work as expected.
> 
> What is going on here?
> Is it something that I am missing, or is it a PHP or QuickForm bug?
> 
> Thanks in advance.
> 
> - Jay
> 
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