[英]Using dynamic keys in forEach loop
I have the following javascript Object 我有以下javascript对象
const items = {
0: {
id: 1,
color: 'blue'
},
1: {
id: 2,
color: 'red'
}
}
I am trying to restructure it so that the keys have an indexed numerical value like so: item1id , item1color , item2id , item2color . 我正在尝试对其进行重组,以使键具有类似这样的索引数字值: item1id , item1color , item2id , item2color 。 Or to be more precise it should look like this in the end:
或者更确切地说,它最终应该看起来像这样:
const restrucuturedItems = {
item1id: 1,
item1color: 'blue',
item2id: 2,
item2color: 'red'
}
I have tried the following, but so far didn't yield positive results: 我已经尝试了以下方法,但到目前为止并未产生积极的结果:
const restrucuturedItems = {}; // should collect the restructured data in one object like so: {item1id: 1, item1color: 'blue', item2id:2, item2color: 'red'}
const restructuredData = Object.keys(items).forEach(key => {
let i = parseInt(key, 10) + 1;
let item = {
item[i]id: 1, // this part is incorrect. it should produce item1id, item2id
item[i]color: 'blue' // this part is incorrect. it should produce item1color, item2color
}
restrucuturedItems.push(item);
});
After hours of research, I still don't know how to write this part correctly. 经过数小时的研究,我仍然不知道如何正确编写此部分。
You shouldn't use push
because you want your restrucuturedItems
to be an object , not an array. 您不应该使用
push
因为您希望restrucuturedItems
是一个对象 ,而不是数组。
Concatenate the i
with the id or color inside the brackets, and use two Object.entries
- one to get the keys and values of each object in the outer object, and one to get the keys and values of each inner object: 将
i
与方括号内的id或颜色连接起来,并使用两个 Object.entries
一个用于获取外部对象中每个对象的键和值,另一个用于获取每个内部对象的键和值:
const items = { 0: { id: 1, color: 'blue' }, 1: { id: 2, color: 'red' } } console.log(Object.entries(items).reduce((a, [num, obj]) => { Object.entries(obj).forEach(([key, val]) => { a['item' + num + key] = val; }); return a; }, {}));
If you really wanted to start at item1id
rather than item0id
, then increment num
initially: 如果您真的想从
item1id
而不是item0id
,那么首先增加num
:
const items = { 0: { id: 1, color: 'blue' }, 1: { id: 2, color: 'red' } } console.log(Object.entries(items).reduce((a, [num, obj]) => { num++; Object.entries(obj).forEach(([key, val]) => { a['item' + num + key] = val; }); return a; }, {}));
const items = { 0: { id: 1, color: 'blue' }, 1: { id: 2, color: 'red' } } const restrucuturedItems = {}; // should collect the restructured data in one object like so: {item1id: 1, item1color: 'blue', item2id:2, item2color: 'red'} const restructuredData = Object.keys(items).forEach(key => { let i = parseInt(key, 10) + 1; restrucuturedItems[`item${i}id`] = 1; restrucuturedItems[`item${i}color`] = 'blue' }); console.log(restrucuturedItems)
First of all, you cannot use push
onto an object. 首先,您不能使用
push
对象。 push
is a method meant for array. push
是用于数组的方法。 Secondly, you can use template string with backtick to construct the property name that you wish 其次,可以使用带有反引号的模板字符串来构造所需的属性名称
a reduce and map function may do the job 缩小和贴图功能可以胜任
var result = Object.values(items).reduce(function (r, val) { // get all the values
var prefix = 'item' + val.id; // construct the prefix like item1, item2
Object.getOwnPropertyNames(val).map(function(key) {
r[prefix + key] = val[key]; // add to the result object
});
return r;
}, {});
https://jsfiddle.net/vw49g8t2/7/ https://jsfiddle.net/vw49g8t2/7/
声明:本站的技术帖子网页,遵循CC BY-SA 4.0协议,如果您需要转载,请注明本站网址或者原文地址。任何问题请咨询:yoyou2525@163.com.