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<?php $arr = array( array( 'id' => 7, 'title' => 'Pongal', 'start' => '2016-05-16' ), array( 'id' => 7, 'title' => 'Mongok', 'start' => '2016-05-16' ) ); foreach($arr as $key => &$val){ $val['color'] = 'red'; } print_r($arr);
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.34, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.31, 8.2.0 - 8.2.26, 8.3.0 - 8.3.14, 8.4.1
Array ( [0] => Array ( [id] => 7 [title] => Pongal [start] => 2016-05-16 [color] => red ) [1] => Array ( [id] => 7 [title] => Mongok [start] => 2016-05-16 [color] => red ) )

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105.8 ms | 409 KiB | 5 Q