如何重命名对象数组中对象的所有键？

Question

Is there a way to change the key names in an array of object?

Code: List of value to change the key name.

var keys = {
    id:'identifier',
    facility:'site',
    status:'info',
    date:'days'
};

Array of object to change the key names

var arrayObj = [{
    id:'jr210',
    facility:'earth',
    status:'sample info',
    date:'Feb 29, 2020'
},
{
    id:'tl980',
    facility:'mars',
    status:'sample info',
    date:'Jan 15, 2020'
}]

Expected output:

var newArrayObj = [{
        identifier:'jr210',
        site:'earth',
        info:'sample info',
        days:'Feb 29, 2020'
    },
    {
        identifier:'tl980',
        site:'mars',
        info:'sample info',
        days:'Jan 15, 2020'
    }]

Answer 1

You can use reduce and Object.entries for the operation.

1. reduce is to re-group the property in the object
2. Object.entries is to retrieve the key and value pairs in the object.

type KeyForFinalResult = 'identifier'|'site'|'info'| 'days'
type KeyForReferenceKeys = 'id' | 'facility' | 'status' | 'date' 

type TempObjectType = {
    [T in KeyForReferenceKeys | string ]: string
}

type FinalObjectType = {
    [T in KeyForFinalResult | string]: string
}

var keys: TempObjectType  = {
    id:'identifier',
    facility:'site',
    status:'info',
    date:'days'
};


var arrayObj:TempObjectType[] = [{
    id:'jr210',
    facility:'earth',
    status:'sample info',
    date:'Feb 29, 2020'
},
{
    id:'tl980',
    facility:'mars',
    status:'sample info',
    date:'Jan 15, 2020'
}]


const result = arrayObj.reduce((finalResult: FinalObjectType[], elem)=>{
    let temp: FinalObjectType = {} as FinalObjectType

    Object.entries(keys).forEach((entry: string[] )=> {
        //each entry: [[key, value],[key1, value1]...]
        temp[entry[1]] = elem[entry[0]]
    })
    
    finalResult.push(temp)
 
    return finalResult
},[])


console.log(result)

Answer 2

This is a map ping task. Like almost every array method map allows a 2nd argument, the thisArg , a context which gets bound to the callback method and thus is accessibly at such a method's apply/call time.

The provided approach implements a callback method remapObjectWithBoundKeys which utilizes its this context as configuration of how to remap each of an object's key. It does so by reduce ing the entries of its key-config and creating a new object by iteratively assign ing new key-value pairs to it.

 const sampleList = [{ id:'jr210', facility:'earth', status:'sample info', date:'Feb 29, 2020', }, { id:'tl980', facility:'mars', status:'sample info', date:'Jan 15, 2020', }]; function remapObjectWithBoundKeys(item) { const keyConfig = this; return Object.entries(keyConfig).reduce((obj, [recentKey, currentKey]) => Object.assign(obj, { [currentKey]: item[recentKey] }), {}); } console.log( sampleList.map(remapObjectWithBoundKeys, { id: 'identifier', facility: 'site', status: 'info', date: 'days', }) );

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The advantage of the implemented method is that it operates independently from a map task. One easily can utilize or re-use it for any kind of object (re)creation...

 function remapObjectWithBoundKeys(item) { const keyConfig = this; return Object.entries(keyConfig).reduce((obj, [recentKey, currentKey]) => Object.assign(obj, { [currentKey]: item[recentKey] }), {}); } const planetType = { id:'tl980', facility:'mars', status:'sample info', date:'Jan 15, 2020', }; const recreatePlanetItem = remapObjectWithBoundKeys.bind({ id: 'identifier', facility: 'site', status: 'info', date: 'days', }); console.log( planetType, recreatePlanetItem(planetType) );

 .as-console-wrapper { min-height: 100%;important: top; 0; }