从多维数组创建集合？

Question

我正在尝试从一些数据数组中创建一个集合:

$myCollection = collect(
    ['product_id' => 1, 'price' => 200, 'discount' => '50'],
    ['product_id' => 2, 'price' => 400, 'discount' => '50']
);

当我循环出去时,我想做:

foreach ($myCollection as $product) {
    echo $product->price;
    echo $product->discount;
}

但是底层元素似乎仍然是数组格式,我怎样才能实现上述输出？

Answer 1

如果您希望内部数组是一个集合,那么您可以这样做:

$myCollection = collect([
    ['product_id' => 1, 'price' => 200, 'discount' => '50'],
    ['product_id' => 2, 'price' => 400, 'discount' => '50']
])->map(function($row) {
    return collect($row);
});

如果您希望内部数组是对象,那么您可以执行以下操作:

$myCollection = collect([
    ['product_id' => 1, 'price' => 200, 'discount' => '50'],
    ['product_id' => 2, 'price' => 400, 'discount' => '50']
])->map(function($row) {
    return (object) $row;
});

您还可以迭代每个结果......

$myCollection = collect([
    ['product_id' => 1, 'price' => 200, 'discount' => '50'],
    ['product_id' => 2, 'price' => 400, 'discount' => '50']
])->map(function($row) {
    return (object) $row;
})->each(function($row) {
    echo sprintf('ProductId: %d, Price: %d, Discount: %s'.PHP_EOL, $row->product_id, $row->price, $row->discount);
});

输出:

ProductId: 1, Price: 200, Discount: 50
ProductId: 2, Price: 400, Discount: 50

Answer 2

很简单，因为您正在收集关联数组的集合，因为您正在收集数组元素，因此集合助手不想修改它，以防您需要它作为数组。

知道这一点，如果你想收集对象，你应该传递一个对象类型的元素。

您可以将对象数据类型转换为数组，如下所示：

$myCollection = collect( (object) array(
     (object)  ['product_id' => 1, 'price' => 200, 'discount' => '50'],
     (object)  ['product_id' => 2, 'price' => 400, 'discount' => '50'])
);

然后你有一个对象的集合！