php klíč v poli existuje
<?php
$search_array = array('first' => null, 'second' => 4);
// returns false
isset($search_array['first']);
// returns true
array_key_exists('first', $search_array);
?>
php klíč existuje
// Here's our fruity array
$fruits = ['apple', 'pear', 'banana'];
// Use it in an `if` statement
if (array_key_exists("banana", $fruits)) {
// Do stuff because `banana` exists
}
// Store it for later use
$exists = array_key_exists("peach", $fruits);
pokud neexistuje klíč json php
<?php
$search_array = array('first' => 1, 'second' => 4);
if (array_key_exists('first', $search_array)) {
echo "The 'first' element is in the array";
}
?>
klíče pole existují v poli
function findKey($array, $keySearch)
{
foreach ($array as $key => $item) {
if ($key == $keySearch) {
echo 'yes, it exists';
return true;
} elseif (is_array($item) && findKey($item, $keySearch)) {
return true;
}
}
return false;
}