我如何从一个对象读取属性，而该对象是另一个对象的属性？

Question

stdClass Object
(
[kind] => youtube#channelListResponse
[etag] => "Fznwjl6JEQdo1MGvHOGaz_YanRU/AwtUznqL5IWQ_LGBo6hPktZlciI"
[pageInfo] => stdClass Object
    (
        [totalResults] => 1
        [resultsPerPage] => 1
    )

[items] => Array
    (
        [0] => stdClass Object
            (
                [kind] => youtube#channel
                [etag] => "Fznwjl6JEQdo1MGvHOGaz_YanRU/89K2C_1kE4Ku8LvtzDJQlV5_e2I"
                [id] => UC-lHJZR3Gqxm24_Vd_AJ5Yw
                [snippet] => stdClass Object
                    (
                        [title] => PewDiePie
                        [description] => I make videos.
                        [publishedAt] => 2010-04-29T10:54:00.000Z
                        [thumbnails] => stdClass Object
                            (
                                [default] => stdClass Object
                                    (
                                        [url] => https://yt3.ggpht.com/a/AGF-l79FVckie4j9WT-4cEW6iu3gPd4GivQf_XNSWg=s88-c-k-c0xffffffff-no-rj-mo
                                        [width] => 88
                                        [height] => 88
                                    )

                                [medium] => stdClass Object
                                    (
                                        [url] => https://yt3.ggpht.com/a/AGF-l79FVckie4j9WT-4cEW6iu3gPd4GivQf_XNSWg=s240-c-k-c0xffffffff-no-rj-mo
                                        [width] => 240
                                        [height] => 240
                                    )

                                [high] => stdClass Object
                                    (
                                        [url] => https://yt3.ggpht.com/a/AGF-l79FVckie4j9WT-4cEW6iu3gPd4GivQf_XNSWg=s800-c-k-c0xffffffff-no-rj-mo
                                        [width] => 800
                                        [height] => 800
                                    )

                            )

                        [localized] => stdClass Object
                            (
                                [title] => PewDiePie
                                [description] => I make videos.
                            )

                        [country] => US
                    )

            )

    )

）

如何获取值（例如，高stdClass对象的url）？

我必须首先创建一个数组，还是可以直接访问此值？我不知道如何从另一个对象获取属性的对象的值。

提前感谢！

Answer 1