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<?php function lambda_filter_empty($entry) { return ($entry !== ''); } $test = array( 'country_id' => '1', 'state' => '', 'city' => '', 'address1' => '', ); $result = array_keys(array_filter($test, "lambda_filter_empty")); var_dump($result); $bool = $result === array("country_id"); var_dump($bool);
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9, 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.25, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.7
array(1) { [0]=> string(10) "country_id" } bool(true)
preferences:
282.69 ms | 406 KiB | 369 Q