JavaScript 对象中的数组？

Question

我试图看看这是否可能，但我找不到我的答案。

我正在尝试使以下内容起作用：

var defaults = {
 'background-color': '#000',
 color: '#fff',
 weekdays: {['sun','mon','tue','wed','thu','fri','sat']}
};

它只是给出了一个错误，我已经尝试使用({...})和[{...}]我希望能够使用以下内容访问工作日：

defaults.weekdays[0];

这可能吗？

Answer 1

杀死大括号。

var defaults = {
 backgroundcolor: '#000',
 color: '#fff',
 weekdays: ['sun','mon','tue','wed','thu','fri','sat']
};

Answer 2

// define
var foo = {
  bar: ['foo', 'bar', 'baz']
};

// access
foo.bar[2]; // will give you 'baz'

Answer 3

 var data = { name: "Ankit", age: 24, workingDay: ["Mon", "Tue", "Wed", "Thu", "Fri"] }; for (const key in data) { if (data.hasOwnProperty(key)) { const element = data[key]; console.log(key+": ", element); } }

Answer 4

 var defaults = { "background-color": "#000", color: "#fff", weekdays: [ {0: 'sun'}, {1: 'mon'}, {2: 'tue'}, {3: 'wed'}, {4: 'thu'}, {5: 'fri'}, {6: 'sat'} ] }; console.log(defaults.weekdays[3]);

Answer 5

关于对象中的多个数组。 例如，您想记录不同课程的模块

var course = {
    InfoTech:["Information Systems","Internet Programming","Software Eng"],
    BusComm:["Commercial Law","Accounting","Financial Mng"],
    Tourism:["Travel Destination","Travel Services","Customer Mng"]
};
console.log(course.Tourism[1]);
console.log(course.BusComm);
console.log(course.InfoTech);

Answer 6

如果你有条理，你可以从一开始就声明整个对象（这个逗号分隔的列表称为对象初始值设定项）：

let myObject = {
    string:   'Galactic Rainbows',
    color:    'HotPink',
    sociopaths: ["Hitler","Stalin","Gates"]
}

或者，一旦你声明了对象，你可以通过给它们赋值来定义它的属性：

let myObject = {};    //this line is the declaration
myObject.string = "Galactic Rainbows";
myObject.color = "HotPink";
myObject.sociopaths = ["Hitler","Stalin","Gates"];

下面的所有示例都假定该对象已被声明（如上所示）

我更喜欢像这样单独声明数组，然后将其分配给对象：

let weekdays = ['sun','mon','tue','wed','thu','fri','sat'];
myObject.weekdays = weekdays;

但是如果你已经声明了对象，那么编码会更快：

myObject.weekdays = ['sun','mon','tue','wed','thu','fri','sat'];

但是您不能像这样将数组数组分配给对象：

myObject.girlsAndBoys[0] = ["John","Frank","Tom"];    //Uncaught TypeError: Cannot set property '1' of undefined
myObject.girtsAndBoys[1] = ["Jill","Sarah","Sally"];   //Uncaught TypeError: Cannot set property '1' of undefined

要将二维数组分配给对象，您有几个选择。 您可以先声明空的二维数组：

myObject.girlsAndBoys    = [[]];
myObject.girlsAndBoys[0] = ["John","Frank","Tom"]; 
myObject.girtsAndBoys[1] = ["Jill","Sarah","Sally"];   

或者您可以逐层进行：

let boys  = ["John","Frank","Tom"];    
let Girls = ["Jill","Sarah","Sally"];
myObject.girlsAndBoys = [[boys],[girls]];

或者，您可以一次完成所有操作（仅在对象声明之后）：

let myObject = {};
myObject.girlsAndBoys = [["John","Frank","Tom"],["Jill","Sarah","Sally"]];
myObject.girlsAndBoys[0][0] == "John";   // returns True

Answer 7

var obj = {
 webSiteName: 'StackOverFlow',
 find: 'anything',
 onDays: ['sun'     // Object "obj" contains array "onDays" 
            ,'mon',
            'tue',
            'wed',
            'thu',
            'fri',
            'sat',
             {name : "jack", age : 34},
              // array "onDays"contains array object "manyNames"
             {manyNames : ["Narayan", "Payal", "Suraj"]}, //                 
           ]
};