php二维数组相同id的数量相加

数组样式

$arr = array(
    array(
       'user_id' => 100,
       'goods_id' => 10,
       'number' => 1,
    ),
    array(
       'user_id' => 100,
       'goods_id' => 10,
       'number' => 2,
    ),
    array(
       'user_id' => 100,
       'goods_id' => 10,
       'number' => 2,
    ),
    array(
       'user_id' => 100,
       'goods_id' => 10,
       'number' => 2,
    ),
);

处理办法

$item=array();
foreach($arr as $k=>$v){
    if(!isset($item[$v['user_id']])){
        $item[$v['user_id']]=$v;
    }else{
        $item[$v['user_id']]['number']+=$v['number'];
    }
}
print_r($item);