我对如何计算数组中的项目感到困惑
代码
// Product ID's to Search
$deposit_items = array( '4359', '4336', '4331', '4320' );
// Loop through the Cart Items
foreach ( $cart_object->get_cart() as $item_values ) {
// Check if the cart contains items with the matching Product ID's
if( in_array( $item_values['product_id'], $deposit_items )) {
// Count number of products in Cart that have matching Product ID's
}
}
我需要返回数组中具有产品 ID 的项目数,如 $deposit_items
最佳答案
像这样
// Product ID's to Search
$deposit_items = array( '4359', '4336', '4331', '4320' );
$cart_items = $cart_object->get_cart();
$cart_product_ids = array_column($cart_items, 'product_id');
$count = count(array_intersect($cart_product_ids, $deposit_items ));
例如
// Product ID's to Search
$deposit_items = array( '4359', '4336', '4331', '4320' );
$cart_items = [
['product_id' => 4359],
['product_id' => 4320]
];
$cart_product_ids = array_column($cart_items, 'product_id');
echo count(array_intersect($cart_product_ids, $deposit_items ));
输出
2
它可以像这样被压缩(Golfed)成一行:
$deposit_items = array( '4359', '4336', '4331', '4320' );
echo count(array_intersect(array_column($cart_object->get_cart(),'product_id'),$deposit_items));
供引用
http://php.net/manual/en/function.array-column.php
http://php.net/manual/en/function.array-intersect.php
数组列,获取那个大的多维数组并返回单个列,使用我的(有点简单)示例:
$cart_items = [
['product_id' => 4359],
['product_id' => 4320],
['product_id' => 333]
];
变成(我加了333,只是为了好玩)
[4359, 4320, 333]
基本上与您的 $deposit_items
格式相同。一旦它们相同,我们就可以使用数组相交,找到数组 1 中出现在第二个数组中的所有项目。在这种情况下,我们需要上述数组项,前提是它们在 $deposit_items
中。一旦我们有了这些,用 count 来计算它们就是一件简单的事情。
进一步说明
print_r([
['product_id' => 4359],
['product_id' => 4320],
['product_id' => 333]
], 'product_id');
输出
[4359, 4320, 333]
然后
print_r(array_intersect([4359, 4320, 333], ['4359', '4336', '4331', '4320']));
输出
[4359, 4320]
然后计数非常简单。
其他内容
巧合的是,如果你想做相反的事情,计算不在 $deposit_items
中的项目,你只需将 array_intersect
替换为 array_diff
即可。
echo count(array_diff(array_column($cart_items, 'product_id'), $deposit_items ));
如果您使用数组 diff 翻转数组,您将获得不在购物车中的存款项目数。
echo count(array_diff($deposit_items, array_column($cart_items, 'product_id')));
干杯!
关于PHP 计算另一个数组中存在的数组项数,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/52791877/