如何将数组转换为此json模式？

I have array something like this

Array
(
     [0] => Array
        (
            [product_id] => 13
            [unit] => 1
            [price] => 20.0000
            [total] => 20.0000
        )

    [1] => Array
        (
            [product_id] => 15
            [unit] => 2
            [price] => 30.0000
            [total] => 10.0000 
        )

)

I was stuck to transform above array to the "ProductList" in the following pattern

array(
     "UserID" => 2,
     "ProductList" => [
         {
             "ProductID"=> 13,
             "Price"=> 20.0000
         }, 
         {
             "ProductID"=> 15,
             "Price"=> 30.0000
         }
     ]
)

I tried like this:

$products = [];
foreach($items as $item) {
    if(!empty($item['product_id'])) {
        $product = '{"ProductID"=>' . $item['product_id'] . '}';
        $products[] = $product;
    }
}

But not the expected result.

You're looking for json_encode(): http://php.net/manual/en/function.json-encode.php

Assign your array to a variable, for example $products, and then you can simply write json_encode($products) to achieve your desired result.

Try this,

$prodlist = array();
$x = 0;
foreach($arrs as $arr) {
    //if ($arr['product_id'] == "" && $arr['price'] == "") continue;
    $prodlist[$x]['Price'] = $arr['price'];
    $prodlist[$x]['ProductID'] = $arr['product_id'];
    $x += 1;
}
$arr2return['user_id'] = $user_id;
$arr2return['ProductList'] = $prodlist;
json_encode($arr2return);