Recursive function not stopping? - php

Question

I created a recursive function to find a key-value in a multidimensional array
Function:
public function find_key_recursive($haystack, $needle) {
foreach($haystack as $key=>$value) {
if(is_array($value)){
$this->find_key_recursive($value, $needle);
} else if($key === $needle) {
return $value;
}
}
}
(Part of) Array:
$oLayoutProperties =
Array
(
[header] => Array
(
[logo_float] => left
[logo_upload] => http://placehold.it/150x100&text=afbeelding
[logo_margin_top] => 0
[searchbar_toggle] => false
[language_toggle] => false
[color] => 0
[font_size] => 12
[background_color] => 0
)
[menu] => Array
(
[menu_type] => full
[menu_align] => left
[menu_position_toggle] => false
[menuheight] => Array
(
[bar_height] => 0
)
[color] => 0
[font_size] => 12
[text_transform] => like_pagetitle
[background_color_hover] => 0
[color_hover] => 0
)
[submenu] => Array
(
[color] => 0
[font-size] => 12
[item_height] => 0
[item_width] => 0
[text-transform] => like_pagetitle
[background_color] => 0
[background_color_hover] => 0
[color_hover] => 0
)
)
I call the function as following:
$oElement_controller->find_key_recursive($oLayoutProperties, 'logo_float');
I validated (using echo's) that the key 'logo_float' indeed gets found, but I don't seem to be able to cancel the recursive function?
I tried the following:
return false;
break;
None of the above seem to work.
How do you stop a recursive function?

Answer 1

You can use a static variable to remember the status between multiple function calls. It makes the function remember the value of the given variable ($needle_value in this example) between multiple calls.
public function find_key_recursive($haystack, $needle){
static $needle_value = null;
if($needle_value != null){
return $needle_value;
}
foreach($haystack as $key=>$value) {
if(is_array($value)){
$this->find_key_recursive($value, $needle);
} else if($key === $needle) {
$needle_value = $value;
return $needle_value;
}
}
}
This function finally returns $needle_value, which is your desired needle in the haystack.

Answer 2

public function find_key_recursive($haystack, $needle) {
foreach($haystack as $key=>$value) {
if(is_array($value)){
var $found = $this->find_key_recursive($value, $needle);
if ($found){
return $found;
}
} else if($key === $needle) {
return $value;
}
}
return false;
}
I haven't touched PHP in a while, but something like this will probably work.

Answer 3

You can put the result in a variable passed by reference, like this:
public function find_key_recursive($haystack, $needle, &$found) {
foreach($haystack as $key => $value) {
if (is_array($value)) {
$this->find_key_recursive($value, $needle, $found);
} else if($key === $needle) {
$found = $value;
return;
}
}
}
$found = false;
$oElement_controller->find_key_recursive($oLayoutProperties, 'logo_float', $found);
if ($found !== false) {
// found!
}