php 二维数组去重合并将相同数量累加

$arr = array(
    array(
       "user_id" => 100,
       "goods_id" => 10,
       "number" => 1,
    ),  
    array(
       "user_id" => 102,
       "goods_id" => 10,
       "number" => 1,
    ),  
    array(
       "user_id" => 102,
       "goods_id" => 10,
       "number" => 1,
    ),  
    array(
       "user_id" => 102,
       "goods_id" => 10,
       "number" => 1,
    ),  
);
 
$result = array();
 
foreach($arr as $val){
    $key = $val["user_id"]."_".$val["goods_id"];
    if(!isset($result[$key])){
        $result[$key] = $val;
    }else{
        $result[$key]["number"] += $val["number"];
    }
}
 
echo "<pre>";
print_r(array_values($result));
echo "</pre>";

运行结果：

Array
(
    [0] => Array
        (
            [user_id] => 100
            [goods_id] => 10
            [number] => 1
        )
 
    [1] => Array
        (
            [user_id] => 102
            [goods_id] => 10
            [number] => 3
        )
 
)