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<?php $headers = array( 'User-Agent' => 'Mozilla', ); $headers = array_change_key_case($headers); // Convert all keys to lower $keyExists = array_key_exists('user-Agent', $headers); var_dump($keyExists);
Output for 7.0.0 - 7.0.23, 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 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
bool(false)
preferences:
91.27 ms | 1513 KiB | 4 Q