我有这个 json 页面: https://www.googleapis.com/books/v1/volumes?q=9789264187061 看起来像这样:
{“种类”:“books#volumes”,“totalItems”:1,“items”:[{
“种类”:“books#volume”,“id”:“Z9i0nRGVYrcC”,“etag”:“6BZ/vrmjoqQ” , "selfLink": " https://www.googleapis.com/books/v1/volumes/Z9i0nRGVYrcC ",
在国家和地方层面刺激创新的政策必须建立并促进创新集群的活力。本书介绍了该领域的政策制定者和学术专家撰写的一系列论文,展示了为什么以及如何在不同的国家背景下做到这一点。", "industryIdentifiers": [ { "type": "ISBN_10", "identifier ": "9264187065" }, { "type": "ISBN_13", "identifier": "9789264187061" } ], "pageCount": 419, "printType": "BOOK", "categories": [ "Business & Economics" ],“averageRating”:1.0,“ratingsCount”:http://bks6.books.google.it/books?id=Z9i0nRGVYrcC&printsec=frontcover&img=1&zoom=5&edge=curl&source=gbs_api ", "缩略图": " http://bks6.books.google.it/books?id= Z9i0nRGVYrcC&printsec=frontcover&img=1&zoom=1&edge=curl&source=gbs_api " }, "language": "en", "previewLink": " http://books.google.it/books?id=Z9i0nRGVYrcC&printsec=frontcover&dq=9789264187061&hl=&cd=1&source =gbs_api ", "infoLink": " http://books.google.it/books?id=Z9i0nRGVYrcC&dq=9789264187061&hl=&source=gbs_api ", "canonicalVolumeLink": " http://books.google.it/books/about /Innovative_Clusters。html?hl=&id=Z9i0nRGVYrcC" }, "saleInfo": { "country": "IT", "saleability": "NOT_FOR_SALE", "isEbook": false }, "accessInfo": { "country": "IT", "viewability": "ALL_PAGES ”,“可嵌入”:真,“publicDomain”:假,“textToSpeechPermission”:“ALLOWED_FOR_ACCESSIBILITY”,“epub”:{“isAvailable”:真,“acsTokenLink”:“ http://books.google.it/books/下载/Innovative_Clusters-sample-epub.acsm?id=Z9i0nRGVYrcC&format=epub&output=acs4_fulfillment_token&dl_type=sample&source=gbs_api " }, "pdf": { "isAvailable": false },"webReaderLink": " http://books.google.it/books/reader?id=Z9i0nRGVYrcC&hl=&printsec=frontcover&output=reader&source=gbs_api", "accessViewStatus": "SAMPLE" }, "searchInfo": { "textSnippet": "本书介绍了该领域的政策制定者和学术专家撰写的一系列论文,展示了为什么以及如何在不同的国家背景。” } } ] }
我必须阅读并定义 $book_title 和 $book_author
“volumeInfo”:{“title”:“创新集群”,“作者”:[“Pim Den Hertog”,“Svend Reme”,
根据上面的代码
回声 $book_title;
应该返回“创新集群”和
回声 $book_author;
应该返回“Pim Den Hertog 和 Svend Reme”