PHP Access a Nested Object Property Using Variable

Question

I am using PHP7.

I have an Object I am trying to parse:

$RECORD = {
    'name' => 'Stephen Brad Taylor', 
    'address' => '432 Cranberry Hills, Pittsburg',
    'phone' => '708 865 456', 
    'Account' => (Object Vendor/Entity/User) {
         'email' => 'INeedThisEmail@pleaseHelp.com' // I want to access this property.
         'id' => 34,
         'accessible' => ['email', 'id]
    } 
}

I have an array which I am using to select certain fields from RECORD :

$fieldnames = [
     'name',
     'address',
     'phone',
     'Account["email"]'
];

I am trying to parse the fieldnames from RECORD as follows:

$data[] 
foreach($fieldnames as $k => $fieldname) {
    $data[k] = $RECORD->$fieldname
}

The method above works for the first-level attributes: name, address, and phone . However, email returns null.

I have tried the following below and none have worked:

$data[k] = RECORD->${$fieldname}

$propertyName = '$RECORD->$fieldname' 
$data[k] = ${$propertyName}

Does anyone know a way to access an object's properties using a string from an object reference ?

Much gratitude <3

Answer 1

You can't use Account["email"] directly as a property accessor, it won't be split up to find the nested property. You need to parse it yourself.

foreach($fieldnames as $k => $fieldname) {
    if (preg_match('/^(.*)\["(.*)"\]$/', $fieldname, $match) {
        $data[$k] = $RECORD->{$match[1]}->{$match[2]};
    } else {
        $data[$k] = $RECORD->$fieldname;
    }
}

Also, you need $ in $k .

This code only works for 1 level deep. If you need to deal with arbitrary levels, you'll have to write a recursive procedure. See How to access and manipulate multi-dimensional array by key names / path? for examples of how to code this.

Answer 2

I use anonymous functions for such cases. (PHP 7.4)

    $index = fn($item) => $item->dotaItem->prop_def_index;
    if (get_class($collection) === Collection::class) {
        $index = fn($item) => $item->prop_def_index;
    }