如何创建一个单独的具有公共 id 的 json 对象数组答案

【问题标题】：how to create a separate array of json object having common id如何创建一个单独的具有公共 id 的 json 对象数组
【发布时间】：2021-02-19 18:38:44
【问题描述】：

大家好，我有情况需要你的帮助，我有一个具有公共 id 的 json 数组，首先我需要从所有 json obj 中获取公共 id，然后将每个公共 json 放置到单独的数组中

var myArray = [ {"id" : 1, "text": "Number one", "time": "16 03 13"},{"id" : 1, "text": "Number two", "time": "14 03 13"},{"id" : 1, "text": "Number three", "time": "13 03 13"},{"id" : 2, "text": "Number one", "time": "13 03 13"}] 


I want output of this object as 

 var myArray = {    
[           
"1" : [
  {"text": "Number one", "time": "16 03 13"}, 
  {"text": "Number two", "time": "14 03 13"},  
  {"text": "Number three", "time": "13 03 13"} 
]
]
[
"2" : [
  {"text": "Number one", "time": "13 03 13"}   
]

]}

I want to place common ID in a each separate JSON array to make 2d array

【问题讨论】：

标签： javascript node.js json arraylist

【解决方案1】：


var myArray = [ {"id" : 1, "text": "Number one", "time": "16 03 13"},{"id" : 1, "text": "Number two", "time": "14 03 13"},{"id" : 1, "text": "Number three", "time": "13 03 13"},{"id" : 2, "text": "Number one", "time": "13 03 13"}] 



const uniqueIds  = myArray.map(elem=>elem.id).filter((value, index, self)=>self.indexOf(value) === index)


const contentsOfId = (id)=>{
    return myArray.filter(elem=>elem.id === id).map(({text,time})=>({text,time}))

}

const results = uniqueIds.map(id =>{

    const obj={}
    obj[id]=contentsOfId(id);
    return obj;

})

输出将是


[{"1":[{"text":"Number one","time":"16 03 13"},{"text":"Number two","time":"14 03 13"},{"text":"Number three","time":"13 03 13"}]},{"2":[{"text":"Number one","time":"13 03 13"}]}]

【讨论】：

【解决方案2】：

您可以线性地实现这一点，而不是使用多个循环。

var myArray = [{ "id": 1, "text": "Number one", "time": "16 03 13" }, { "id": 1, "text": "Number two", "time": "14 03 13" }, { "id": 1, "text": "Number three", "time": "13 03 13" }, { "id": 2, "text": "Number one", "time": "13 03 13" }]
const outputArray = {}
myArray.forEach((ele)=>{
    if(outputArray[ele.id]){
       outputArray[ele.id] = [...outputArray[ele.id], {...ele}]
    } else {
       outputArray[ele.id] = [ele]
    }
});
console.log(outputArray)

输出将是

{ '1':[ { id: 1, text: 'Number one', time: '16 03 13' },
        { id: 1, text: 'Number two', time: '14 03 13' },
        { id: 1, text: 'Number three', time: '13 03 13' }
       ],
  '2': [ { id: 2, text: 'Number one', time: '13 03 13' } ]
 }

【讨论】：