从数组合并json然后重新创建数组

Question

I have an array as follows

Array
(
    [photo] => Array
        (
            [0] => {"file_name":"Penguins.jpg", "content_type": "image/jpeg", "tmp_path": "/var/www/servergreek.com/public_html/www/imgscript/tmp/0048699176"}
            [1] => {"file_name":"Penguins.jpg", "sha256" : "7e5bdd023b6cf21efe42a8ec90bc1993fc853980d4b564688e5ac2d28c64223c" , "size" : "777835"}
            [2] => {"file_name":"sample.png", "content_type": "image/png", "tmp_path": "/var/www/servergreek.com/public_html/www/imgscript/tmp/0048699177"}
            [3] => {"file_name":"sample.png", "sha256" : "e6aa1bf1cdb7ca546576cecd61973939be4f1dc8cec3a4f3b49b31d8f60e202f" , "size" : "278383"}
        )

    [submit] => Upload
)

I want to create an array as follows

Array
(
    [photo] => Array
        (
            [0] => {"file_name":"Penguins.jpg", "content_type": "image/jpeg", "tmp_path": "/var/www/servergreek.com/public_html/www/imgscript/tmp/0048699176" , "sha256" : "7e5bdd023b6cf21efe42a8ec90bc1993fc853980d4b564688e5ac2d28c64223c" , "size" : "777835"}

            [1] => {"file_name":"sample.png", "content_type": "image/png", "tmp_path": "/var/www/servergreek.com/public_html/www/imgscript/tmp/0048699177" , "sha256" : "e6aa1bf1cdb7ca546576cecd61973939be4f1dc8cec3a4f3b49b31d8f60e202f" , "size" : "278383"}
        )

    [submit] => Upload
)

Answer 1

Here is a solution which uses array_reduce to build a map with decoded JSON objects, keyed by their file_name values, and then applies array_map to convert the objects in that map back to JSON strings.

The intermediate array_values turns the associative array into an indexed array:

$data['photo'] = array_map('json_encode', array_values(array_reduce($data['photo'], 
    function($dict, $json) {
        $obj = json_decode($json, true);
        $key = $obj['file_name'];
        if (!isset($dict[$key])) $dict[$key] = [];
        $dict[$key] += $obj; // merging arrays with plus operator
        return $dict;
    }, []))
);

This solution does not necessitate that two related JSON strings are consecutive. It will work if the array is in any order. It also works if there would be more than two JSON strings with the same file_name property, joining whatever other properties are in those extra JSON strings.

See it run on eval.in.