PHP：如何在树状 JSON 结构中递归搜索 ID 并返回包含所有先前 ID 的路径

Question

I have a specific problem that I can't handle. I have a JSON file and I need to find the id in it. I need to get all previous id when id is found.

Find id 51. Results: 51, 12962, 1101, 1100

Thank you in advance for your help.

{
"status":"SUCCESS",
"data":[
    {
        "id":"12522",
        "name":"name 1",
    },
    {
        "id":"13081",
        "name":"name 2",
    },
    {
        "id":"1100",
        "name":"name 3",
        "childs":[
            {
                "id":"11591",
                "name":"name 4",
                "childs":[
                    {
                        "id":"12382",
                        "name":"name 5",
                    },
                    {
                        "id":"48",
                        "name":"name 6",
                    },
                    {
                        "id":"11590",
                        "name":"name 7",
                    }
                ]
            },
            {
                "id":"1101",
                "name":"name 8",
                "childs":[
                    {
                        "id":"11589",
                        "name":"name 9",
                    },
                    {
                        "id":"12962",
                        "name":"name 10",
                        "childs":[
                            {
                                "id":"51",
                                "name":"name 11",
                            }
                        ]
                    }
                ]
            }

....

Answer 1

I've stripped down the JSON input for this example, but the result is an array holding the IDs up until the id you're looking for (or empty if the id hasn't been found). The code is annotated so you can see what it actually does. Basically, I'm using a recursive function, meaning a function that calls itself, passing on the current stack of ids on each call.

<?php
$data = json_decode( '[{"id": "1234"},{"id": "4567"},{"id": "1100","childs": [{"id": "7890"},{"id": "1101","childs": [{"id": "12962","childs": [{"id": "51"}]}]}]}]' );

// recursively go through the data, searching for the id
function findIdRecursive( $id, $data, $stack = array() ) {
    foreach ( $data as $d ) {
        // this object corresponds to the id
        if ( $d->id === $id ) {
            $stack[] = $id;
            break;
        } else if ( isset( $d->childs ) ) {
            // recursively go through this object's children
            $childStack = findIdRecursive( $id, $d->childs, $stack );
            if( in_array( $id, $childStack ) ) {
                // if the id is present in the child stack, return this path
                $stack = array_merge( [ $d->id ], $childStack );
                break;
            }
        }
    }

    return $stack;
}

// [ 51, 12962, 1101, 1100 ]
var_dump( array_reverse( findIdRecursive( "51", $data ) ) );