I have values passed c and 3 from $_GET variable, which I want to look up in an array as values and retrieve their keys. How can I search through the array to return accurate keys?
The code below
<?php
$array1 = array(0 => 'a', 1 => 'c', 2 => 'c');
$array2 = array(0 => '3', 1 => '2', 2 => '3');
$key1 = array_search('c', $array1);
$key2 = array_search('3', $array2);
?>
returns
$key1 = 1;
$key2 = 0;
though I am expecting
$key1 = 2;
$key2 = 2;
foreach ($array1 as $key => $value) {
if ($value == 'c' && $array2[$key] == '3') {
echo "The key you are looking for is $key";
break;
}
}
I'm pretty sure there's a saner way to do whatever you're trying to do though.
The function returned exactly as it should have. The first occurrence of value 'c' exists at index 1 in $array1 and the value '3' has its first occurrence at index 0 in $array2
This behavior is documented in the php docs on array_search and it even supplies you with an alternative if you don't like it:
If needle is found in haystack more than once, the first matching key is returned. To return the keys for all matching values, use array_keys() with the optional search_value parameter instead.
If you want to find the last key that has that value, you could reverse your array first.
$array1 = array(0 => 'a', 1 => 'c', 2 => 'c');
$array2 = array(0 => '3', 1 => '2', 2 => '3');
$key1 = array_search('c', $array1);
$key2 = array_search('3', $array2);
var_dump($key1,$key2); //output: int(1) int(0)
$key1 = array_search('c', array_reverse($array1, true));
$key2 = array_search('3', array_reverse($array2, true));
var_dump($key1,$key2); //output: int(2) int(2)
Perhaps something like:
<?php
// for specificly 2 arrays
function search_matching($match1, $match2, array $array1, array $array2) {
foreach($array1 as $key1 => $value1) {
// we may want to add $strict = false argument to distinguish between == and === match
// see http://php.net/manual/en/function.array-search.php
if($value1 == $match1 and isset($array2[$key1]) and $array2[$key1] == $match2) {
return $key1;
}
}
return null;
}
// unlimited
function search_matching(array($matches), array $array/*, ...*/) {
if( count($matches) != func_num_args() - 1)
throw new \Exception("Number of values to match must be the same as the number of supplied arrays");
$arrays = func_get_args();
array_shift($arrays); // remove $matches
$array = array_unshift($arrays); // array to be iterated
foreach($array as $key => $value) {
if($value == $matches[0]) {
$matches = true;
foreach($arrays as $keyA => $valueA) {
if(! isset($arrays[$key] or $valueA != $matches[$keyA+1]) {
$matches = false;
break;
}
}
if($matches)
return $key;
}
}
return null;
}
The functions are created with numerical keys in mind.
They could be made cleaner by offloading some functionality to other function, but I wanted to keep it concise and together for the sake of easily seeing how it works
