[英]Subtract row values in Array2 from specific row values in Array1
我想從$array1
的stocks
中減去$array2
的quantity
。
$array1= ([product_id]=>4, [stocks]=>20)
$array2= ([product_id]=>4, [quantity]=>3)
So that would be:
$array1= ([0]=> 4, [1] => 20);
$array2= ([0]=> 4, [1] => 3);
然后輸出應該是:
$array1= ([0]=> 4, [1] => 17);
根據您的要求,以下內容將滿足您的要求:
if($array1['product_id'] == $array2['product_id']) {
$array1['stocks'] -= $array2['quantity'];
}
如果你需要循環一個更大的陣列,那么我所提供的只是更大拼圖的一部分。
您的數組結構與多個記錄看起來略有不同,代碼以丑陋的方式運行。 我假設你在談論這樣的事情:
$array1 = array(
0=>array('product_id'=>4, 'stocks'=>20),
1=>array('product_id'=>5, 'stocks'=>60));
$array2 = array(
0=>array('product_id'=>4, 'quantity'=>3)
1=>array('product_id'=>5, 'quantity'=>30));
...這是一個多維數組(通常用於從數據庫中提取的記錄)。
foreach($array1 as $key=>$value){
foreach($array2 as $key2=>$value2) {
if($value['product_id']==$value2['product_id']){
$value['stocks'] -= $value2['quantity'];
//optimization to avoid searching this again.
unset($array2[$key]);
}
}}
Jesse的答案沒有經過測試,也沒有提供所需的輸出,因為“stock”數組沒有被修改 - 數組的副本正在循環中被修改 - 所以如果你試圖將結果打印到屏幕上,沒有變化。
要通過引用進行修改,請在第一個循環中使用&
之前的值變量。
unset()
鍵也必須來自內循環才能准確。
另外,如果“sales”“product_id”是唯一的,那么在匹配時打破內部循環將提高性能。 (這就是array_search()
工作原理。)
代碼:( 演示 )
$stocks = [
['product_id'=>2, 'stocks'=>50],
['product_id'=>3, 'stocks'=>100],
['product_id'=>4, 'stocks'=>20],
['product_id'=>5, 'stocks'=>60]
];
$sales = [
['product_id'=>4, 'quantity'=>3],
['product_id'=>5, 'quantity'=>30]
];
foreach ($stocks as &$row) { // modify by reference
foreach ($sales as $k => $row2) { // search for product_id match
if ($row['product_id'] == $row2['product_id']) {
$row['stocks'] -= $row2['quantity']; // subtract
unset($sales[$k]); // eliminate match from lookup array
break; // assuming $sales['product_id'] values are unique
}
}
}
var_export($stocks);
輸出:
array (
0 =>
array (
'product_id' => 2,
'stocks' => 50,
),
1 =>
array (
'product_id' => 3,
'stocks' => 100,
),
2 =>
array (
'product_id' => 4,
'stocks' => 17,
),
3 =>
array (
'product_id' => 5,
'stocks' => 30,
),
)
或者,您可以將sales數組轉換為flattened,product_id-keyed數組以用作查找。
代碼:( 演示 )
$keyed = array_column($sales, 'quantity', 'product_id');
var_export($keyed);
echo "\n---\n";
foreach ($stocks as &$row) { // modify by reference
if (isset($keyed[$row['product_id']])) { // search for product_id match
$row['stocks'] -= $keyed[$row['product_id']]; // subtract
}
}
var_export($stocks);
輸出:
array (
4 => 3,
5 => 30,
)
---
array (
0 =>
array (
'product_id' => 2,
'stocks' => 50,
),
1 =>
array (
'product_id' => 3,
'stocks' => 100,
),
2 =>
array (
'product_id' => 4,
'stocks' => 17,
),
3 =>
array (
'product_id' => 5,
'stocks' => 30,
),
)
聲明:本站的技術帖子網頁,遵循CC BY-SA 4.0協議,如果您需要轉載,請注明本站網址或者原文地址。任何問題請咨詢:yoyou2525@163.com.