我无法使用 array_key_exist 为 json 响应获取指定的键

Question

$status_key ="status"$response = {"error":false,"data":{"id":16420728,"order_id":"5000","mobile_no":"9995088810","amount":20,"balance":46.89,"status":"failure","tnx_id":"","response":"Transaction Failed"}}"$result = json_decode($response);这打印：{     ["error"]=> bool(false)     ["data"]=> object(stdClass)#24 (8) {         ["id"]=> int(16420728)         ["order_id"]=> string(4) "5000"         ["mobile_no"]=> string(10) "9995088810"         ["amount"]=> int(20)         ["balance"]=> float(46.89)         ["status"]=> string(7) "failure"         ["tnx_id"]=> string(0) ""         ["response"]=> string(18) "Transaction Failed"     }}现在我正在检查指定的密钥var_dump(array_key_exist(status_key,result));当我执行var_dump()此功能时，它返回"bool(false)"