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<?php $test = ['a' => 1, 'b' => null]; echo "array_key_exists:\n"; echo array_key_exists('a', $test) ? "a: found\n" : "a: not found\n"; echo array_key_exists('b', $test) ? "b: found\n" : "b: not found\n"; echo "\n\nisset:\n"; echo isset($test['a']) ? "a: found\n" : "a: not found\n"; echo isset($test['b']) ? "b: found\n" : "b: not found\n"; echo "\n\nempty:\n"; echo empty($test['a']) ? "a: found\n" : "a: not found\n"; echo empty($test['b']) ? "b: found\n" : "b: not found\n";
Output for 5.5.0 - 5.5.35, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 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 - 8.1.30, 8.2.0 - 8.2.24, 8.3.0 - 8.3.12
array_key_exists: a: found b: found isset: a: found b: not found empty: a: not found b: found
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81.22 ms | 408 KiB | 5 Q