使用php拉出json数据的“列”

Question

I'm trying to pull specific data from this json:

[
    {
        "@context": "http://vocab.tokyometroapp.jp/context_odpt_Railway.jsonld",
        "@id": "urn:ucode:_00001C000000000000010000030C46B1",
        "@type": "odpt:Railway",
        "owl:sameAs": "odpt.Railway:TokyoMetro.Yurakucho",
        "dc:title": "有楽町",
        "odpt:stationOrder": [
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Wakoshi",
                "odpt:index": 0
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.ChikatetsuNarimasu",
                "odpt:index": 1
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.ChikatetsuAkatsuka",
                "odpt:index": 2
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Heiwadai",
                "odpt:index": 3
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Hikawadai",
                "odpt:index": 4
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.KotakeMukaihara",
                "odpt:index": 5
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Senkawa",
                "odpt:index": 6
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Kanamecho",
                "odpt:index": 7
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Ikebukuro",
                "odpt:index": 8
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.HigashiIkebukuro",
                "odpt:index": 9
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Gokokuji",
                "odpt:index": 10
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Edogawabashi",
                "odpt:index": 11
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Iidabashi",
                "odpt:index": 12
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Ichigaya",
                "odpt:index": 13
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Kojimachi",
                "odpt:index": 14
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Nagatacho",
                "odpt:index": 15
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Sakuradamon",
                "odpt:index": 16
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Yurakucho",
                "odpt:index": 17
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.GinzaItchome",
                "odpt:index": 18
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Shintomicho",
                "odpt:index": 19
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Tsukishima",
                "odpt:index": 20
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Toyosu",
                "odpt:index": 21
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.Tatsumi",
                "odpt:index": 22
            },
            {
                "odpt:station": "odpt.Station:TokyoMetro.Yurakucho.ShinKiba",
                "odpt:index": 23
            }
        ],
        "odpt:travelTime": 

~~~~~~~~~~~~~~~~~~~~~snip~~~~~~~~~~~~~~~~~~

what I'm trying to get is the station names, like TokyoMetro.Yurakucho.ShinKiba.

I've tried:

$json = file_get_contents($url.$info.$token);
$data = json_decode($json);
$stations = array($data->opdt.station);
var_dump($stations);

but I'm not getting anything back:

array(1) { [0]=> string(7) "station" }

is there a way to grab this particular 'column' of data? I'm more used to database queries.

Thanks so much!

Answer 1

Since there are multiple stations, you have to iterate through the array and put them in an array of station names.

$json = file_get_contents($url.$info.$token);
$data = json_decode($json, true);
$stations = array();
foreach ($data[0]['odpt:stationOrder'] as $station) {
    $name = $station['odpt:station'];
    $parts = explode(':', $name);
    $stations[] = $parts[1]; // Only care about the part after `odpt.Station:`
}

var_dump($stations);