--- id: 56533eb9ac21ba0edf2244cc title: 访问嵌套对象 challengeType: 1 videoUrl: 'https://scrimba.com/c/cRnRnfa' forumTopicId: 16161 dashedName: accessing-nested-objects --- # --description-- 通过串联起来的点操作符或中括号操作符来访问对象的嵌套属性。 下面是一个嵌套的对象: ```js var ourStorage = { "desk": { "drawer": "stapler" }, "cabinet": { "top drawer": { "folder1": "a file", "folder2": "secrets" }, "bottom drawer": "soda" } }; ourStorage.cabinet["top drawer"].folder2; // "secrets" ourStorage.desk.drawer; // "stapler" ``` # --instructions-- 读取`myStorage`对象,将`glove box`属性的内容赋值给变量`gloveBoxContents`。在适用的地方使用点操作符来访问属性,否则使用中括号操作符。 # --hints-- `gloveBoxContents`应该等于"maps"。 ```js assert(gloveBoxContents === 'maps'); ``` 应使用点操作符和中括号操作符来访问`myStorage`。 ```js assert(/=\s*myStorage\.car\.inside\[\s*("|')glove box\1\s*\]/g.test(code)); ``` # --seed-- ## --after-user-code-- ```js (function(x) { if(typeof x != 'undefined') { return "gloveBoxContents = " + x; } return "gloveBoxContents is undefined"; })(gloveBoxContents); ``` ## --seed-contents-- ```js // Setup var myStorage = { "car": { "inside": { "glove box": "maps", "passenger seat": "crumbs" }, "outside": { "trunk": "jack" } } }; var gloveBoxContents = undefined; // Change this line ``` # --solutions-- ```js var myStorage = { "car":{ "inside":{ "glove box":"maps", "passenger seat":"crumbs" }, "outside":{ "trunk":"jack" } } }; var gloveBoxContents = myStorage.car.inside["glove box"]; ```