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<?php $array = json_decode('{"1":"1","2":"1","3":"1","4":"1","12":"1"}' , true); var_dump($array); var_dump(array_key_exists("12", $array));
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.24, 8.2.0 - 8.2.11
array(5) { [1]=> string(1) "1" [2]=> string(1) "1" [3]=> string(1) "1" [4]=> string(1) "1" [12]=> string(1) "1" } bool(true)
preferences:
55.36 ms | 407 KiB | 5 Q