Changing the key name in an array of objects?

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
  };
});
    
console.log("arrayObj = " + JSON.stringify(arrayObj));

You can't change a property name, you have to add the value with a new name and delete the old property:

for (var i = 0; i < arrayObj.length; i++) {
  arrayObj[i].stroke = arrayObj[i].key1;
  delete arrayObj[i].key1;
}

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"}]

You don't change a key name. You can assign a new key name/value and then remove the previous key if you want. In your example:

var arrayObj = [{key1,'value1', key2:'value2'},{key1,'value1', key2:'value2'}];
var o = arrayObj[0];   // get first object
var val = o.key1;      // get current value
o.stroke = val;        // assign to new key
delete o.key1;         // remove previous key

If you wanted to do that for all the objects in your main array, you would just put that in a loop that iterates over the contents of your array. I've put more intermediate assignments in here than neccessary just to document what's going on.

Or a shortened version in a loop:

for (var i = 0; i < arrayObj.length; i++) {
    var o = arrayObj[i];
    o.stroke = o.key1;
    delete o.key1;
}

function changeKey(originalKey, newKey, arr)
{
  var newArr = [];
  for(var i = 0; i < arr.length; i++)
  {
    var obj = arr[i];
    obj[newKey] = obj[originalKey];
    delete(obj[originalKey]);
    newArr.push(obj);
  }
  return newArr;
}

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)