Reference JSON object w/PHP by element value

Question

I'm not sure if I'm even asking the question correctly, but here goes.

I have a JSON file that looks more or less like this:

[{
"programName": "Entrepreneurial Skills",
"description": "The Certificate in Entrepreneurial Skills 1 provides you, as a small business owner/operator, with the essential skills and competitive strategies to help your enterprise thrive.",
"faculty": "School of Business and Economics",
"department": "Marketing, International Business and Entrepreneurship",
"id": 79,
"parentId": 0,
"relatedIds": [3, 4, 5, 16, 26, 27],
"tabGroup": 0,
"credentialType": "Certificate",
"credentialName": "Certificate in Entrepreneurial Skills",
"programCode": "",
"programOption": "",
"delivery": "distance",
"campus": "",
"length": { "credits": 15, "courses": 0, "weeks": 0, "months": 0, "years": 0, "varies": false },
"intakeDates": "",
"internationalFriendly": false,
"careers": "",
"priorityResult": false,
"url": "distance/programs/business-management/certificate-in-entrepreneurial-skills-1",
"imageUrl": "",
"tags": ""
}, {
"programName": "Environmental Economics and Management",
"description": "Attain a broad knowledge of the business environment, advanced management skills and specialized knowledge in environmental economics and sustainability.",
"faculty": "School of Business and Economics",
"department": "Economics",
"id": 80,
"parentId": 0,
"relatedIds": [45,67,88],
"tabGroup": 4,
"credentialType": "Master",
"credentialName": "Master in Environmental Economics and Management",
"programCode": "MEEM",
"programOption": "",
"delivery": "campus",
"campus": "",
"length": { "credits": 0, "courses": 0, "weeks": 0, "months": 0, "years": 2, "varies": false },
"intakeDates": "",
"internationalFriendly": true,
"careers": ["Economic sustainable management"],
"priorityResult": true,
"url": "programs/catalogue/masters-degrees-environmental-economics-and-management",
"imageUrl": "meem-msceem-banner39755.jpg",
"tags": ""
},{ etc }]

I am putting that file into an array like so:

    $programData = json_decode($json, true);

and then subsequently stepping through it and storing it in a $content variable that will be displayed in HTML. It more or less looks like this (simplified):

foreach ($programData as $key => $value) {
$content.='<h4 class="credentialName">'.$value['credentialName'].'</h4>';
$content.='<p class="lead">'.$value['description'].'</p>';
etc...
}

Within that foreach, I reach a point where I have another foreach going through the relatedProgram items. These are integers that are meant to match up - and display - the URL/title of the related ID in the JSON array. These IDs do not match the key of the item in the JSON array. This is where I'm having a problem. How do I find the key of the $programData -> $id 3 (for example), then get the $url and $programName from that item, from within the foreach?

I've googled and overflowed to the nth degree and I'm stumped. Any help would be very appreciated!

Possible duplicate of [How do I extract data from JSON with PHP?](http://stackoverflow.com/questions/29308898/how-do-i-extract-data-from-json-with-php) — miken32, Apr 05 '17 at 23:20
you mean where's the `id` key?, haven't you tried `$value['id']` its under there, then make your `if` block — Kevin, Apr 05 '17 at 23:21
Well, that's faulty design. Use the ID's on the outer row and then create a function or use `array_filter()` to search elements of the outer list, returning on the row that has the ID you're looking for. — Jared Farrish, Apr 05 '17 at 23:45
Very possibly faulty design - this is my first time trying this, so I was mostly winging it when building the JSON. I had looked online at a variety of sites that explained the schema, but it didn't seem apparent a 'best practice' approach to this particular setup, so I just did what I thought was right at the time. — oliverh72, Apr 06 '17 at 15:40
@Ghost I meant - I want the numeric locations in the original array $programData where the $relatedIds (3, 4, 5, etc) match the $id. Basically, I want to be able to grab the data from the program where the id is 3 and I thought the easiest way would be to find the key of that element within the full array - for example, it would be [2]. Then I could simply refer to it within my second foreach, echoing that to the screen. I hope that makes it more clear — oliverh72, Apr 06 '17 at 15:59

score 1 · Accepted Answer · answered Apr 05 '17 at 23:24

I suppose you could post-process your array to get those IDs out of the items:

<?php
foreach($programData as $k=>$v) {
    $newProgramData[$v["id"]] = $v;
}

Now your programs are indexed by their ID in $newProgramData.

Sample code:

<?php
$json = '[{"id":45,"name":"foo"},{"id":234,"name":"bar"},{"id":52,"name":"baz"}]';
$data = json_decode($json, true);
foreach ($data as $v) { $newData[$v["id"]] = $v; }
print_r($newData);

Output:

Array
(
    [45] => Array
        (
            [id] => 45
            [name] => foo
        )

    [234] => Array
        (
            [id] => 234
            [name] => bar
        )

    [52] => Array
        (
            [id] => 52
            [name] => baz
        )

)

going to give this a try and see if I can make it work. Thanks! — oliverh72, Apr 06 '17 at 15:44
This is exactly what I needed! Worked flawlessly, thank you so much! — oliverh72, Apr 06 '17 at 16:10

Reference JSON object w/PHP by element value

1 Answers1