在数组第一个插入元素：
$goods_class = [ '0' => [ 'class_id' => '1', 'class_name' => '鱼' ], '1' => [ 'class_id' => '2', 'class_name' => '虾' ], ]; $arr = [ 'class_id' => '0', 'class_name' => '全部商品' ]; array_unshift($goods_class, $arr); print_r($goods_class); 打印结果： [ '0' => [ 'class_id' => '0', 'class_name' => '全部商品' ], '1' => [ 'class_id' => '1', 'class_name' => '鱼' ], '2' => [ 'class_id' => '2', 'class_name' => '虾' ], ]