嵌套对象和数组解构 [英] Nested object and array destructuring

问题描述

我的对象包括一个也包含对象的嵌套数组，从这个数组我只会喜欢几个字段。

我可以做嵌套对象的破坏，罚款，数组解析不错，但不在一起？

我目前的尝试如下所示：

  var data = {
 title：title1，
 bar：asdf，
 innerData：[
 {
 title：inner-title1，
 foo：asdf
}，
 {
 title：inner-title2，
 foo：asdf
} 
] 
}; 
 
 var {title，innerData：[{title}]} = data; 
 
 console.log（title）; $（$ var $ title）of $ data $ {
 
} {
 console.log（title）; 
} 
  

但是收到一条消息说 innerData没有定义。

我想要的结果可能是：

  {
 title：title1，
 innerData：[
 {
 title：inner-title1
}，
 {
标题：inner-title2
} 
] 
}; 
  

解决方案

您可以将变量名称调整为除定义 innerData ;使用 .map（）或 JSON.stringify（）， JSON.parse（）过滤标题属性从 innerData 对象

  var {title，titles = data.innerData.map（o =>（{title：o.title}））} = data; 
  

维护 innerData 可以使用的变量名对象的数组解构

  var [title，innerData] = [data.title，data.innerData.map（o => （{标题：o.title}））]; 
  

使用 JSON.stringify（）， JSON.parse（）

  var [title，innerData] = JSON。解析（JSON.stringify（[data.title，data.innerData]，[title]））; 
  

---

编辑

如果要求是在数据中创建一个包含所有标题属性的数组，则可以使用 JSON.stringify（） with replacer array set to [title] ， JSON.parse ），spread元素

  var data =标题：title1，bar：asdf，innerData：[{title：inner-title1，foo：asdf}，{title：inner-title2，foo：asdf}]}; var innerData = JSON.parse（JSON.stringify（[data，... data.innerData]，[title]））console.log（innerData）;  

/ div>

I am trying to convert an object to a leaner version using destructuring.

My object includes a nested array which also contains objects, from this array I would only like a few fields.

I can do the nested object destructuring fine, and the array destructuring fine but not together?

My current try looks like this:

var data = {
    title: "title1",
    bar: "asdf",
    innerData: [
       {
        title: "inner-title1",
        foo: "asdf"
       },
       {
        title: "inner-title2",
        foo: "asdf"
       }
    ]
};

var { title, innerData: [ { title} ] } = data;

console.log(title);

for (var { title} of innerData) {
  console.log(title);
}

But get a message saying innerData is not defined.

The outcome I would like might be:

{
    title: "title1",
    innerData: [
       {
        title: "inner-title1"
       },
       {
        title: "inner-title2"
       }
    ]
};

解决方案

You can adjust the variable name to an identifier other than defined innerData ; use .map() or JSON.stringify(), JSON.parse() to filter title property from innerData objects

var {title, titles = data.innerData.map(o => ({title:o.title}))} = data;

to maintain innerData variable name you can use array destructuring of object

var [title, innerData] = [data.title, data.innerData.map(o => ({title:o.title}))];

using JSON.stringify(), JSON.parse()

var [title, innerData] = JSON.parse(JSON.stringify([data.title, data.innerData], ["title"]));

---

Edit

If requirement is to create an array containing all title properties within data you can use JSON.stringify() with replacer array set to ["title"], JSON.parse(), spread element

var data = {
    title: "title1",
    bar: "asdf",
    innerData: [
       {
        title: "inner-title1",
        foo: "asdf"
       },
       {
        title: "inner-title2",
        foo: "asdf"
       }
    ]
};

var innerData = JSON.parse(JSON.stringify([data, ...data.innerData], ["title"]))
                                                                      
console.log(innerData);

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