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<?php $order_info = [ "success" => 1, "return" => [ "100010973975966" => [ "pair" => "doge_btc" // etc.. ] ] ]; $order_id = key($order_info['return']); echo $order_id;
Output for 5.6.38, 7.0.33, 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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
100010973975966
preferences:
150.29 ms | 408 KiB | 5 Q