How to use "for" to work with data in an array whose amount of varied data is unknown?

Question

I have the following JSON variable resulting from a php query:

$json_string = '[
  {
    "id": 1,
    "name": "Jogos para PC",
    "products": [
      {
        "id": 34,
        "name": "Grand Theft Auto V"
      },
      {
        "id": 59,
        "name": "Bloodstained Ritual of the Night"
      },
      {
        "id": 60,
        "name": "F1 2019 - Anniversary Edition"
      },
      {
        "id": 62,
        "name": "PLAYERUNKNOWN\'S BATTLEGROUNDS"
      },
      {
        "id": 64,
        "name": "Batman: Arkham Knight"
      }
    ],
    "tags": []
  },
  {
    "id": 2,
    "name": "Jogos Mobile",
    "products": [
      {
        "id": 3,
        "name": "Clash of Clãs"
      },
      {
        "id": 4,
        "name": "Mobile Legends"
      }
    ],
    "tags": []
  },
  {
    "id": 4,
    "name": "PlayStation Store",
    "products": [
      {
        "id": 39,
        "name": "PSN Gift Card - R$ 30,00"
      },
      {
        "id": 40,
        "name": "PSN Gift Card - R$ 60,00"
      }
    ],
    "tags": []
  }
]';

I use the command $array = json_decode($json_string); to work with the following code:

$array = json_decode($json_string);
foreach ($array as $value)
    {
        for ($row = 0; $row < 5; $row++) {
        echo $value->products[($row)]->name .' - ID: '. $value->products[($row)]->id .'<br>';
    }
}

This returns me the names of the games as follows:

Grand Theft Auto V - ID: 34<br>
Bloodstained Ritual of the Night - ID: 59<br>
F1 2019 - Anniversary Edition - ID: 60<br>
PLAYERUNKNOWN'S BATTLEGROUNDS - ID: 62<br>
Batman: Arkham Knight - ID: 64<br>
Clash of Clãs - ID: 3<br>
Mobile Legends - ID: 4<br>

I used $row < 5 because I know that the largest amount of games in one of the lists is 5, so all appear, the problem is when the list has less than 5 games because PHP returns an error:

Therefore, considering that he did not know the amount of games in each of the sets, what would be the correct way to list all the games in the array?

Answer 1

You can always use the count() to get the array size.

---

So if you’re using $value->products[($row)], can use the count($value->products) to get how many there are.

for ($row = 0; $row < count($value->products); $row++) {
    echo $value->products[($row)]->name .' - ID: '. $value->products[($row)]->id .'<br>';
}

---

You can also use the foreach, which was the same one you used before (you used foreach ($array as $value) before, so you know how this works).

foreach ($value->products as $product) {
    echo $product->name .' - ID: '. $product->id .'<br>';
}

Answer 2

The value of the key products is also an array, as it is bounded by [ and ]:

"products": [
    ... etc
]

So just walk it with foreach also:

foreach ($array as $value) {
    foreach ($value->products as $product) {
        echo $product->name .' - ID: '. $product->id .'<br>';
    }
}

Exit:

Grand Theft Auto V - ID: 34<br>
Bloodstained Ritual of the Night - ID: 59<br>
F1 2019 - Anniversary Edition - ID: 60<br>
PLAYERUNKNOWN'S BATTLEGROUNDS - ID: 62<br>
Batman: Arkham Knight - ID: 64<br>
Clash of Clãs - ID: 3<br>
Mobile Legends - ID: 4<br>
PSN Gift Card - R$ 30,00 - ID: 39<br>
PSN Gift Card - R$ 60,00 - ID: 40<br>