I have an array within an array.
$array = [
['foo' => 'bar', 'value' => 'America'],
['value' => 'England', 'bar' => 'food'],
];
How do I check if 'America' exists in the array? The America array could be any key, and there could be any number of subarrays, so a generalized solution please.
Looking on the php manual, I see in_array()
, but that only works for the top layer. so something like in_array("America", $a)
would not work.
A general solution would be:
function deep_in_array($needle, $haystack) {
if(in_array($needle, $haystack)) {
return true;
}
foreach($haystack as $element) {
if(is_array($element) && deep_in_array($needle, $element))
return true;
}
return false;
}
The reason why I chose to use in_array
and a loop is: Before I examine deeper levels of the array structure, I make sure, that the searched value is not in the current level. This way, I hope the code to be faster than doing some kind of depth-first search method.
Of course if your array is always 2 dimensional and you only want to search in this kind of arrays, then this is faster:
function in_2d_array($needle, $haystack) {
foreach($haystack as $element) {
if(in_array($needle, $element))
return true;
}
return false;
}