Adding multiple values to same key in array php - php

Question

I want to add multiple values into arrays, for same key.
I have this code:
public function getOnlySellers()
{
$sellers[] = array();
foreach ($this->getProducts() as $product) {
$product_id = $product['product_id'];
$getseller = $this->getSellerbyProduct($product_id);
$sellers[$getseller] = $product_id;
}
return $sellers;
}
Here I have for example: seller 1 with values: 100 and 101
Seller 2 with values: 107
But on my code, on seller 1 for example, is showing only last value 101, but not both.
What is wrong ?
And the call code:
$call = $this->cart->getOnlySellers();
foreach ($call as $seller => $products)
{
$show = "$show <br> $seller has value $products";
}
Thanks!

Answer 1

You could add an array of product ids to your $sellers array, allowing you to assign multiple product_ids to each seller. This [] operator will push the $product_id onto a new array at $sellers[$getseller].
$sellers[$getseller][] = $product_id;
The full code then being:
public function getOnlySellers()
{
$sellers[] = array();
foreach ($this->getProducts() as $product) {
$product_id = $product['product_id'];
$getseller = $this->getSellerbyProduct($product_id);
$sellers[$getseller][] = $product_id;
}
return $sellers;
}
When you output the values, you could use implode to glue the product ids together:
$call = $this->cart->getOnlySellers();
foreach ($call as $seller => $products)
{
$show = "$show <br> $seller has value ".implode(', ', $products);
}