Changing the key name in an array of objects?

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How can I change the key name in an array of objects?

var arrayObj = [{key1:'value1', key2:'value2'},{key1:'value1', key2:'value2'}];

How can I change each key1 to stroke so that I get:

var arrayObj = [{stroke:'value1', key2:'value2'},{stroke:'value1', key2:'value2'}];
11 Answers

In recent JavaScript (and TypeScript), use destructuring with rest syntax, spread syntax, and array map to replace one of the key strings in an array of objects.

const arrayOfObj = [{
  key1: 'value1',
  key2: 'value2'
}, {
  key1: 'value1',
  key2: 'value2'
}];
const newArrayOfObj = arrayOfObj.map(({
  key1: stroke,
  ...rest
}) => ({
  stroke,
  ...rest
}));

console.log(newArrayOfObj);

ES6 map() method:

let arrayObj = [{key1:'value1', key2:'value2'},{key1:'value1', key2:'value2'}];

arrayObj = arrayObj.map(item => {
      return {
        stroke: item.key1,
        key2: item.key2
      };
    });

just one line of code needed with ES6

try following code :

arrayObj.map(({ stroke, key2 }) => ({ yourNewKey: stroke, yourNewKey2: key2 }));

const company =  [{ id:"1", name:"somename"},{ id:"1", name:"somename"}]

company.map(({ id, name }) => ({ companyId: id, companyName: name }));

// output
//[{ companyId:"1", companyName:"somename"},{ companyId:"1", //companyName:"somename"}]

pure javascript

var array=[{oldkey:'oldkeyvalue',oldkey2:'oldkey2'}]
var result=array.map(({ oldkey: newkey, ...rest }) => ({ newkey, ...rest }));
console.log(result)

lodash or underscore js

//Lodash/underscore.js
_.map(array,(({ oldkey: newkey, ...rest }))=>({ oldkey: newkey, ...rest }))

The above technique cant set string name

eg:full name or last name

wrong way:

name:full name

right way

name:full_name

you can achieve string object in same way using map

array.map((x)=>{
var y={};
//also use spread operator if necessary but key want to remove manually

y['full name']=x['name'];
return y;
})

Another option, when you have other arrays, and they have objects with different keys names and your objects they have equal size.

function convertKeys (arr) {
  const newFormat = arr.map((value) => {
    const arrFormat = Object.values(value)
    return {
      newKey1: arrFormat[0],
      newKey2: arrFormat[1]
    }
  })
}

In array.map, i converted the object to an array and got the values ​​by their index.

You can use an immutable way of changing an object. You can also add new key-value pairs to the object

let arrayOfObj = [{id:"0",name:'myName'},{id:"2",name:'myNewName'}]
const newArr = arrayOfObj.map(item => ({ ...item, id : Number(item.id),someRandomKey:'RandomValue' }))
console.log(newArr)

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