[Resolved] Can't obtain $filterAt

[ppowell]

	/**
	 * Filter results according to given instruction
	 *
	 * @access private
	 * @param object $result (reference)
	 * @return object $filteredResult
	 */
	function &filterResults(&$result) {										// STATIC OBJECT ARRAY METHOD
		global $section;
		list($willFilterByLetter, $letter) = array($_REQUEST['willFilterByLetter'], $_REQUEST['letter']);
		if ($willFilterByLetter && preg_match('/[a-z]/i', $letter)) {
		 $filterAt = $this->filterAtArray[$section];
		 array_walk($result, create_function('&$a', 'global $filterAt, $letter; if (!preg_match("/^$letter/i", $a->$filterAt)) unset($a);'));
		}
		return $result;
	}

I can't obtain $filterAt within the create_function()-created function within array_walk(), yet I can obtain $letter. I verified this via using print_r to show that $letter exists while $filterAt does not, however, $filterAt DOES exist prior to array_walk().

Could someone tell me what I did wrong?

Thanx
Phil

[rehfeld]

i dont have an answer to your question, but noticed something else you might want to be aware of

the way your using
preg_match('/[a-z]/i', $letter)

may not work as you might expect. all that will do is tell you if $letter contains a letter. judging by the variable name, maybe you want to check to make sure that it ONLY contains a single letter, and nothing else.

^[a-z]$

or 1 or more letters, nothing else

^[a-z]+$

or use ctype_alpha()

[ppowell]

great, thanx I didn't think of that to be honest, but you're right.

Still can't figure out the problem with create_function() though.

Phil

[sidney]

i believe you have to pass $filterAt to the function as the optional third argument

 array_walk($result, create_function('&$a', 'global $filterAt, $letter; if (!preg_match("/^$letter/i", $a->$filterAt)) unset($a);'),$filterAt); 

[ppowell]

Sorry I tried that, to no avail:

	/**
	 * Filter results according to given instruction
	 *
	 * @access private
	 * @param object $result (reference)
	 * @return object $filteredResult
	 */
	function &filterResults(&$result) {										// STATIC OBJECT ARRAY METHOD
		global $section;
		list($willFilterByLetter, $letter) = array($_REQUEST['willFilterByLetter'], $_REQUEST['letter']);
		if (is_array($result) && @sizeof($result) > 0 && $willFilterByLetter && preg_match('/[a-z]/i', $letter)) {
		 $filterAt = $this->getFilterAtArray($section);			// ONLY RETRIEVE THE VALUE OF $this->filterAtArray[$section]
		 list($GLOBALS['filterAt'], $GLOBALS['letter']) = array($filterAt, $letter);
		 global $letter, $filterAt;
		 $array = array($letter, $filterAt);
		 array_walk($result, create_function('&$a', 'list($letter, $filterAt) = $array; print_r("letter = $letter and filterAt = $filterAt<P>"); if (!preg_match("/^$letter/i", $a->$filterAt)) unset($a);'), $array);
		}
		return $result;
	}

The results of the print_r() are as follows:

letter = and filterAt =

I'm at my wit's end, what do I do?

Phil

[ppowell]

Well, it appears array_walk() just doesn't cut it in this case, so I gave up and brute-forced the change via a for loop:

	/**
	 * Filter results according to given instruction
	 *
	 * @access private
	 * @param object $result (optional)
	 * @return object $filteredResult
	 */
	function &filterResults($result = '') {										// STATIC OBJECT ARRAY METHOD
		global $section;
		list($willFilterByLetter, $letter) = array($_REQUEST['willFilterByLetter'], $_REQUEST['letter']);
		if (is_array($result) && @sizeof($result) > 0 && $willFilterByLetter && strlen($letter) == 1 && ctype_alpha($letter)) {
		 $filterAt = $this->getFilterAtArray($section);			// ONLY RETRIEVE THE VALUE OF $this->filterAtArray[$section]
		 $filteredResult = array();
		 for ($i = 0; $i < @sizeof($result); $i++) 
		  if (strpos(strtolower($result[$i]->$filterAt), strtolower($letter)) === 0) array_push($filteredResult, $result[$i]);
		 @reset($filteredResult);
		}
		return $filteredResult;
	}

Phil

[tank]

Your code prior to the last post where you are trying to pass the $array parameter would not work because you still had '&$a' . That is only one and you would need three parameters (key, value, and one for $array).

How or why did you figure out that array_walk() does not help you?

[ppowell]

That's not it, dude, sorry.

It won't work apparently because array_walk() cannot unset array elements, something I'm totally used to doing using Java with Vector elements (Vector.removeElementAt(int i) ).

The PHP manual states that you are not to unset an array element within array_walk(), thus, that was the problem.

Phil

[tank]

Yeah, hay man, dude...like that's really cool.

It still wouldn't have worked using array_walk() the way you had it.

How did you figure it out man? Finally read the F**king manual or what?

Why am I talking this way 🙂

[ppowell]

Since that response is not addressed in the manual, I would not be able to provide a viable answer, perhaps you can.

Thanks for your help

Phil