You can use a mix of .map and the ... spread operator

You can set the value after you've created your new array

let array = [{id:1,name:'One'}, {id:2, name:'Two'}, {id:3, name: 'Three'}];

let array2 = array.map(a => {return {...a}})

array2.find(a => a.id == 2).name = "Not Two";

console.log(array);
console.log(array2);

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Or you can do it in the .map

let array = [{id:1,name:'One'}, {id:2, name:'Two'}, {id:3, name: 'Three'}];

let array2 = array.map(a => {
  var returnValue = {...a};

  if (a.id == 2) {
    returnValue.name = "Not Two";
  }

  return returnValue
})


console.log(array);
console.log(array2);

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You can use Object.assign() with spread syntax ...

const arrayOfObjects = [{
  x: 'foo'
}, {
  y: 'bar'
}];

const obj = {
  hello: 'world'
};

var result = Object.assign({}, obj, ...arrayOfObjects);
console.log(result)

You're probably looking for map

What you need is array.map(element => element.obj)

Here's what's wrong with your attempts:

• console.log([...array].obj): You're spreading the array into a new array, and then you're logging the obj property of the new array, which is undefined, as expected

• console.log([...array.obj]): You're trying to spread the obj property of array, which is also undefined, meaning you're trying to spread undefined, which throws you an error