Howto loop through JSON in PHP

Question

I have been reading up on posts regarding this topic, but can't for the life of me read this JSON string in PHP.

I want to fetch "summary, descripton, start, end" for each events.

 {
  "pages": {
    "current": 1,
    "total": 1
  },
  "events": [
    {
      "calendar_id": "cal_1",
      "event_uid": "evt_1",
      "summary": "Test",
      "description": "",
      "start": "2016-07-07T04:00:00Z",
      "end": "2016-07-07T05:00:00Z",
      "deleted": false,
      "created": "2016-07-07T04:48:30Z",
      "updated": "2016-07-07T04:51:26Z",
      "actions": {
        "delete": "event_uid"
      },
      "participation_status": "accepted",
      "attendees": [],
      "transparency": "opaque",
      "status": "confirmed",
      "categories": [],
      "recurring": false
    },
    {
      "calendar_id": "cal_1",
      "event_uid": "evt_2",
      "summary": "hyttetur langøyene",
      "description": "",
      "start": "2016-07-08",
      "end": "2016-07-09",
      "deleted": false,
      "created": "2016-07-07T07:11:21Z",
      "updated": "2016-07-07T07:11:21Z",
      "actions": {
        "delete": "event_uid"
      },
      "participation_status": "accepted",
      "attendees": [],
      "transparency": "transparent",
      "status": "confirmed",
      "categories": [],
      "recurring": false
    }
  ]
}

Does the JSON syntax look OK? Any help creating a foreach-loop would be very much appreciated!

var_dump for json_decode:

string(2819) "{"pages":{"current":1,"total":1},"events":[{"calendar_id":"cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw","event_uid":"evt_external_577d536cd42960ce5b87c9bf","summary":"Ullevål","description":"","start":"2016-07-04T08:30:00Z","end":"2016-07-04T09:30:00Z","deleted":false,"created":"2016-07-04T11:21:41Z","updated":"2016-07-04T11:21:41Z","actions":{"delete":"event_uid"},"location":{"description":"Bygg6 2 etasje"},"participation_status":"accepted","attendees":[],"transparency":"opaque","status":"confirmed","categories":[],"recurring":false},{"calendar_id":"cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw","event_uid":"evt_external_577ddfced42960ce5b88ad2d","summary":"Test","description":"","start":"2016-07-07T04:00:00Z","end":"2016-07-07T05:00:00Z","deleted":false,"created":"2016-07-07T04:48:30Z","updated":"2016-07-07T04:51:26Z","actions":{"delete":"event_uid"},"participation_status":"accepted","attendees":[],"transparency":"opaque","status":"confirmed","categories":[],"recurring":false},{"calendar_id":"cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw","event_uid":"evt_external_577de0edd42960ce5b88ad9f","summary":"Ny","description":"","start":"2016-07-07T06:00:00Z","end":"2016-07-07T07:00:00Z","deleted":false,"created":"2016-07-07T04:53:55Z","updated":"2016-07-07T04:56:13Z","actions":{"delete":"event_uid"},"location":{"description":"Sted"},"participation_status":"accepted","attendees":[],"transparency":"opaque","status":"confirmed","categories":[],"recurring":false},{"calendar_id":"cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ","event_uid":"evt_external_577e0098d42960ce5b88c9fe","summary":"siste arbeidsdag!","description":"","start":"2016-07-08","end":"2016-07-09","deleted":false,"created":"2016-07-07T07:11:20Z","updated":"2016-07-07T07:11:20Z","actions":{"delete":"event_uid"},"participation_status":"accepted","attendees":[],"transparency":"transparent","status":"confirmed","categories":[],"recurring":false},{"calendar_id":"cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ","event_uid":"evt_external_577e0099d42960ce5b88c9ff","summary":"hyttetur langøyene","description":"","start":"2016-07-08","end":"2016-07-09","deleted":false,"created":"2016-07-07T07:11:21Z","updated":"2016-07-07T07:11:21Z","actions":{"delete":"event_uid"},"participation_status":"accepted","attendees":[],"transparency":"transparent","status":"confirmed","categories":[],"recurring":false},{"calendar_id":"cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ","event_uid":"evt_external_577e01c1d42960ce5b88ca92","summary":"sykkeltur?","description":"","start":"2016-07-09","end":"2016-07-10","deleted":false,"created":"2016-07-07T07:16:17Z","updated":"2016-07-07T07:16:17Z","actions":{"delete":"event_uid"},"participation_status":"accepted","attendees":[],"transparency":"transparent","status":"confirmed","categories":[],"recurring":false}]}"

print_r for json_decode:

{
pages: {
current: 1,
total: 1
},
events: [
{
calendar_id: "cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw",
event_uid: "evt_external_577d536cd42960ce5b87c9bf",
summary: "Ullevål",
description: "",
start: "2016-07-04T08:30:00Z",
end: "2016-07-04T09:30:00Z",
deleted: false,
created: "2016-07-04T11:21:41Z",
updated: "2016-07-04T11:21:41Z",
actions: {
delete: "event_uid"
},
location: {
description: "Bygg6 2 etasje"
},
participation_status: "accepted",
attendees: [ ],
transparency: "opaque",
status: "confirmed",
categories: [ ],
recurring: false
},
{
calendar_id: "cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw",
event_uid: "evt_external_577ddfced42960ce5b88ad2d",
summary: "Test",
description: "",
start: "2016-07-07T04:00:00Z",
end: "2016-07-07T05:00:00Z",
deleted: false,
created: "2016-07-07T04:48:30Z",
updated: "2016-07-07T04:51:26Z",
actions: {
delete: "event_uid"
},
participation_status: "accepted",
attendees: [ ],
transparency: "opaque",
status: "confirmed",
categories: [ ],
recurring: false
},
{
calendar_id: "cal_V31TZmjRXTMhAAQD_wckNgeNBT7QOZkRF4PXqqw",
event_uid: "evt_external_577de0edd42960ce5b88ad9f",
summary: "Ny",
description: "",
start: "2016-07-07T06:00:00Z",
end: "2016-07-07T07:00:00Z",
deleted: false,
created: "2016-07-07T04:53:55Z",
updated: "2016-07-07T04:56:13Z",
actions: {
delete: "event_uid"
},
location: {
description: "Sted"
},
participation_status: "accepted",
attendees: [ ],
transparency: "opaque",
status: "confirmed",
categories: [ ],
recurring: false
},
{
calendar_id: "cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ",
event_uid: "evt_external_577e0098d42960ce5b88c9fe",
summary: "siste arbeidsdag!",
description: "",
start: "2016-07-08",
end: "2016-07-09",
deleted: false,
created: "2016-07-07T07:11:20Z",
updated: "2016-07-07T07:11:20Z",
actions: {
delete: "event_uid"
},
participation_status: "accepted",
attendees: [ ],
transparency: "transparent",
status: "confirmed",
categories: [ ],
recurring: false
},
{
calendar_id: "cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ",
event_uid: "evt_external_577e0099d42960ce5b88c9ff",
summary: "hyttetur langøyene",
description: "",
start: "2016-07-08",
end: "2016-07-09",
deleted: false,
created: "2016-07-07T07:11:21Z",
updated: "2016-07-07T07:11:21Z",
actions: {
delete: "event_uid"
},
participation_status: "accepted",
attendees: [ ],
transparency: "transparent",
status: "confirmed",
categories: [ ],
recurring: false
},
{
calendar_id: "cal_V31TZmjRXTMhAAQD_WS4wF1Ceg4RMLThLSHGbRQ",
event_uid: "evt_external_577e01c1d42960ce5b88ca92",
summary: "sykkeltur?",
description: "",
start: "2016-07-09",
end: "2016-07-10",
deleted: false,
created: "2016-07-07T07:16:17Z",
updated: "2016-07-07T07:16:17Z",
actions: {
delete: "event_uid"
},
participation_status: "accepted",
attendees: [ ],
transparency: "transparent",
status: "confirmed",
categories: [ ],
recurring: false
}
]
}

Show us the code sample that supposedly decodes that JSON string. It doesn't make sense for "print_r for json_decode" to give this result. — deceze
– deceze ♦, Commented Jul 7, 2016 at 9:17
FWIW, if you json_decode a string and var_dump the result and it says string(2819) "{"..., that means the original JSON must have been double encoded (a JSON encoded JSON string), and you need to JSON-decode it twice. Which is obviously madness and needs to be fixed at the source. — deceze
– deceze ♦, Commented Jul 7, 2016 at 9:20
Thank you so much @deceze Double madness decoding fixed my issue! — Jonny
– Jonny, Commented Jul 7, 2016 at 9:38

Andreas Scheibleger · Accepted Answer · 2016-07-07 08:15:39Z

3

First decode the json:

$data = json_decode($yourJsonString);

Then iterate the events and access properties if your json could be decoded correctly:

if ($data !== null) {
    foreach ($data->events as $event) {
        $summary = $event->summary;
        $description = $event->description;
        $start = $event->start;
        $end = $event->end;
    }
}

edited Jul 7, 2016 at 8:15

answered Jul 7, 2016 at 8:04

Andreas Scheibleger

2972 silver badges8 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

Anwar Over a year ago

you missed a closing parenthesis for your foreach.

Anwar Over a year ago

I would also check if json_decode($string) did not returned null before looping through the array. In fact, json_decode returns null if the json string is not correct (forbidden characters, wrong format, ...).

Jonny Over a year ago

I tried Andreas excample, with closing parenthesis, but it did not work. json_decode is returning the json string I posted in my first post. I also added a "echo "test";" inside the foreach, but this did not get printed. It seems like the foreach loop isn't traversed.

Andreas Scheibleger Over a year ago

I added the null check and missing paranthesis, thanks. @Jonny: json_decode should return an object in your case. $yourJsonString should contain the json string you posted in your question.

Jonny Over a year ago

json_decode does return the object OK. However the foreach loop does not work.

|

Mulan · Accepted Answer · 2016-07-07 08:10:50Z

You need to json_decode it. Then you can use something like array_reduce to extract the data you want

Here is your data

$json = <<<'EOD'
{
  "pages": {
    "current": 1,
    "total": 1
  },
  "events": [
    {
      "calendar_id": "cal_1",
      "event_uid": "evt_1",
      "summary": "Test",
      "description": "",
      "start": "2016-07-07T04:00:00Z",
      "end": "2016-07-07T05:00:00Z",
      "deleted": false,
      "created": "2016-07-07T04:48:30Z",
      "updated": "2016-07-07T04:51:26Z",
      "actions": {
        "delete": "event_uid"
      },
      "participation_status": "accepted",
      "attendees": [],
      "transparency": "opaque",
      "status": "confirmed",
      "categories": [],
      "recurring": false
    },
    {
      "calendar_id": "cal_1",
      "event_uid": "evt_2",
      "summary": "hyttetur langøyene",
      "description": "",
      "start": "2016-07-08",
      "end": "2016-07-09",
      "deleted": false,
      "created": "2016-07-07T07:11:21Z",
      "updated": "2016-07-07T07:11:21Z",
      "actions": {
        "delete": "event_uid"
      },
      "participation_status": "accepted",
      "attendees": [],
      "transparency": "transparent",
      "status": "confirmed",
      "categories": [],
      "recurring": false
    }
  ]
}
EOD;

Now run this to decode an manipulate the data

$data = json_decode($json);

$events = array_reduce($data->events, function($out,$e) {
  return array_merge($out, [[
    'summary' => $e->summary,
    'description' => $e->description,
    'start' => $e->start,
    'end' => $e->end
  ]]);
}, []);

print_r($events);

Output

// Array
// (
//     [0] => Array
//         (
//             [summary] => Test
//             [description] => 
//             [start] => 2016-07-07T04:00:00Z
//             [end] => 2016-07-07T05:00:00Z
//         )
//     [1] => Array
//         (
//             [summary] => hyttetur langøyene
//             [description] => 
//             [start] => 2016-07-08
//             [end] => 2016-07-09
//         )
// )

I'm afraid this didn't work eighter. My code: <?php $output = exec ( 'python cgi-bin/cal.py' ); $data = json_decode($output); $events = array_reduce($data->events, function($out,$e) { return array_merge($out, [[ 'summary' => $e->summary, 'description' => $e->description, 'start' => $e->start, 'end' => $e->end ]]); }, []); print_r($events); ?>

Collectives™ on Stack Overflow

Howto loop through JSON in PHP

2 Answers 2

7 Comments

1 Comment

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

2 Answers 2

7 Comments

1 Comment

Your Answer

Sign up or log in

Post as a guest

Related