Child Key

A Child Key is the key for a field in a parent array. WP Data Sync API allows use of a child key only when iterating an array. Child key is optional and not used in all situations.

Array with Child Key

The Source Key is ImageSet and the Child Key is url.

array(
    ImageSet => array(
        0 => array{
            url    => 'https://website.com/image-1.jpg',
            width  => 600,
            height => 300
        ),
        1 => array{
            url    => 'https://website.com/image-2.jpg',
            width  => 600,
            height => 300
        ),
        2 => array{
            url    => 'https://website.com/image-3.jpg',
            width  => 600,
            height => 300
        )
    )
);

Configuring Array with Child Key

Returns

https://website.com/image-1.jpg