如何使用PHP中的foreach循环将特定值存储到$ _POST数组内的另一个数组中

I am having following values in an array as I did print_r($_POST);

Array
 (
   [prod_category] => 2
   [prod_for] => 2
   [prod_brand] => 1
   [prod_name] => this is a product
   [prod_price] => 100
   [prod_discount] => 102
   [prod_sizes] => s,m,l,xl,xxl,xxxl,41,42,43,44,45
   [prod_colors] => orange,white,red,blue
   [prod_description] => this is a demo product descrption
   [prod_stock] => 100
 )

What I want to do is store the value [prod_sizes] => s,m,l,xl,xxl,xxxl,41,42,43,44,45 which is in the array into a new array variable using foreach loop, so it looks like

Array
 (
   [0] => s
   [1] => m
   [2] => l
   [3] => xl
   [4] => xxl
   [5] => xxxl
   [6] => 41
   [7] => 42
   [8] => 43
   [9] => 44
   [9] => 45
 )

How to achieve it I am using the following code:

$sizes = $temp = array();
foreach ($_POST as $key => $_POST["prod_sizes"])
    {
        $temp = explode(',', $_POST["prod_sizes"]);
        $sizes[] =  $temp[0];
    }
print_r($sizes);

But i am getting output something like this which was not expected.

Array
(
  [0] => 2
  [1] => 2
  [2] => 1
  [3] => this is a product
  [4] => 100
  [5] => 102
  [6] => s
  [7] => orange
  [8] => this is a demo product descrption
  [9] => 100
)

In above values it's only showing the 1st values encountered in each variable.

Anyone can help me with this logic,

Thanks in advance

You do not need any loop here.

Just do:

$sizes = explode(',', $_POST["prod_sizes"]);