Get value of object array-CodePudding

I have the following json:

$data = '{"code":"08261",
          "currency":"EUR", 
          "packs":[ {"amount":0.05,"measure":"g","price":73.0}, 
                    {"amount":0.1,"measure":"g","price":108.0}, 
                    {"amount":0.25,"measure":"g","price":154.0}, 
                    {"amount":0.5,"measure":"g","price":296.0}, 
                    {"amount":1.0,"measure":"g","price":394.0}, 
                    {"amount":2.5,"measure":"g","price":771.0}, 
                    {"amount":5.0,"measure":"g","price":1142.0}, 
                    {"amount":10.0,"measure":"g","price":1693.0}]}';

I can get the value of code and currency as follows:

// Option 1: through the use of an array.
$jsonArray = json_decode($data,true);

$code =  $jsonArray['code'];

// Option 2: through the use of an object.
$jsonObj = json_decode($data);

$code = $jsonObj->code;

How can I get the price for the following packs where the:

amount is '1.0' and measure is 'g'
amount is '5.0' and measure is 'g'
amount is '10.0' and measure is 'g'

CodePudding user response：

If you convert the json into nested arrays (passing true to the $associative parameter of json_decode, you can then use array_filter to filter the packs to find the values you want:

$data = '{"code":"08261",
          "currency":"EUR", 
          "packs":[ {"amount":0.05,"measure":"g","price":73.0}, 
                    {"amount":0.1,"measure":"g","price":108.0}, 
                    {"amount":0.25,"measure":"g","price":154.0}, 
                    {"amount":0.5,"measure":"g","price":296.0}, 
                    {"amount":1.0,"measure":"g","price":394.0}, 
                    {"amount":2.5,"measure":"g","price":771.0}, 
                    {"amount":5.0,"measure":"g","price":1142.0}, 
                    {"amount":10.0,"measure":"g","price":1693.0}]}'; 

function get_price($data, $amount, $measure) {
    $values = array_filter($data['packs'], function ($a) use ($measure, $amount) {
        return $a['amount'] == $amount && $a['measure'] == $measure;
    });
    if (count($values)) return reset($values)['price'];
    return 0;
}

$data = json_decode($data, true);

echo get_price($data, 1.0, 'g') . PHP_EOL;
echo get_price($data, 5.0, 'g') . PHP_EOL;
echo get_price($data, 10.0, 'g') . PHP_EOL;

Output:

394
1142
1693