向對象添加新屬性

Question

我有一個javascript對象，用作具有鍵值對的地圖類型。

當從控制器注入值時，將發生此映射的填充：

var people = {"2":"Brad","3":"Antonio","5":"Stacy","6":"Marry","1":"Jim"}

我想創建一個新的對象，但又有一個條目，即偽代碼

var new_people = people + {11: "John"}

我嘗試先將人復制到新人，然后再：

new_people.\"11\" = "John"

和

new_people."11" = "John"

兩者都會產生故障。 雖然任何字符串而不是數字都可以

new_people.anystring = "John"

var new_people = {"2":"Brad","3":"Antonio","5":"Stacy","6":"Marry","1":"Jim", "anystring":"John"}

Answer 1

您可以使用索引：

new_people['11'] = 'John';

Answer 2

您只需要向該對象添加一個鍵值：

people['11'] = "John";

如果密鑰是有效的標識符名稱（而不是數字），則可以使用以下代碼：

people.key = "John";

如果它不是有效的變量名，則必須使用索引：

people["~!#$#$#HV"] ="some value";

Answer 3

您會遇到問題，因為變量在存儲對象時會保留引用。 通過對new_people進行變異，您也在對人進行變異。

var people = {"1":"James"}
console.log(people);       // Object {1: "James"}
var new_people = people;
new_people["2"] = "Jimmy";
console.log(people);       // Object {1: "James", 2: "Jimmy"}
console.log(new_people);   // Object {1: "James", 2: "Jimmy"}

您需要先克隆對象，然后再對克隆進行突變，以免影響原始對象。

一種簡單的方法是使用underscore.jsextend （）方法，如下所示：

var new_people = _.extend({}, people, {"2": "Jimmy"});
console.log(people);       // Object {1: "James"}
console.log(new_people);   // Object {1: "James", 2: "Jimmy"}

或類似地，使用jQuery這樣的 extend（）：

var new_people = $.extend({}, people, {"2": "Jimmy"});
console.log(people);       // Object {1: "James"}
console.log(new_people);   // Object {1: "James", 2: "Jimmy"}

Answer 4

@Gandalf StormCrow這是代碼： jsfiddle

var people = {"2":"Brad","3":"Antonio","5":"Stacy","6":"Marry","1":"Jim"};

var newpeople = {"11": "John"};
jQuery.extend(people, newpeople);
//Now: people = {"2":"Brad","3":"Antonio","5":"Stacy","6":"Marry","1":"Jim","11": "John"}

for(var i in people){
  alert(people[i]);  
};