我有一个关联数组的数组
aa[] = ('Tires'=>100, 'Oil'=>10, 'Spark Plugs'=>4 ); aa[] = ('Tires'=>454, 'Oil'=>43, 'Spark Plugs'=>3 ); aa[] = ('Tires'=>34, 'Oil'=>55, 'Spark Plugs'=>44 ); aa[] = ('Tires'=>454, 'Oil'=>43, 'Spark Plugs'=>45 ); aa[] = ('Tires'=>34, 'Oil'=>55, 'Spark Plugs'=>433 ); aa[] = ('Tires'=>23, 'Oil'=>33, 'Spark Plugs'=>44 );
两个问题
如何按照字段“Oil”删除重复项 是否有可以提供回调函数作为自定义比较器的array_unique?
如何按照自定义字段“Spark Plugs”排序