php - JSON オブジェクト解析 PHP

Question

PHP で JSON オブジェクトを解析する方法がわかりません。

私は Google API からこのオブジェクトを持っています (アドレスの詳細を削除しました!):

stdClass Object (
    [routes] => Array (
        [0] => stdClass Object (
            [bounds] => stdClass Object (
                [northeast] => stdClass Object (
                   [lat] => 0.000000
                   [lng] => 0.000000
                )
                [southwest] => stdClass Object (
                    [lat] => 0.000000
                    [lng] => 0.00000
                )
            )
            [copyrights] => Map data ©2013 Google
            [legs] => Array (
                [0] => stdClass Object (
                    [distance] => stdClass Object (
                    [text] => 1 ft
                    [value] => 0
                )
                [duration] => stdClass Object (
                    [text] => 1 min
                    [value] => 0
                )
                [end_address] => xxxx
                [end_location] => stdClass Object (
                [lat] => 0.0000
                [lng] => 0.0000
            )
            [start_address] => xx
            [start_location] => stdClass Object (
                [lat] => 0.0000
                [lng] => 0.0000
            )
        [steps] => Array (
            [0] => stdClass Object (
                [distance] => stdClass Object (
                    [text] => 1 ft
                    [value] => 0
                )
            [duration] => stdClass Object (
            [text] => 1 min
            [value] => 0
        )
        [end_location] => stdClass Object (
            [lat] => 0.0000
            [lng] => 0.0000
        )
        [html_instructions] => xxx
        [polyline] => stdClass Object (
            [points] => wcrnIpdvH
        )
        [start_location] => stdClass Object (
            [lat] => 1.234567
            [lng] => 1.234567
        )
        [travel_mode] => DRIVING
        )
        )
        [via_waypoint] => Array (
        )
        )
    )
    [overview_polyline] => stdClass Object (
        [points] => wcrnIpdvH
    )
    [summary] => xx
        [warnings] => Array (
        )
        [waypoint_order] => Array (
        )
        )
    )
    [status] => OK
)

私が残した最後の緯度と経度を取得したい[lat] => 1.234567 [lng] => 1.234567

これを行うことで距離を取得する方法を考え出しました：

$directions = json_decode($return);
$distance = $directions->routes[0]->legs[0]->distance->text;

しかし、経度と緯度を取得することは私を困惑させました。

JSON について少し説明できれば、さらに感謝します。