Change / rename object or exchange content or name

Question

I have the following code and want to change the names or to switsch the value, but i have no idea how it can work and is easy

var employees = [{firstName: "Richter", lastName: "Johnas"},


{firstName: "Leibig", lastName: "Linda"},
{firstName: "Schneider", lastName: "Mariane"},
];
console.log("\n> Should display [{firstName: 'Johnas', lastName: 'Richter'}, {firstName: 'Linda', lastName: 'Leibig'}, {firstName: 'Mariane', lastName: 'Schneider'}]");
console.log(revertFirstNamesAndLastNames(employees));`

And i want to change the firstname to lastname and lastname to firstname.

What attempts have you made to solve the problem on your own ? — Hunter McMillen, May 11 '18 at 17:48
i've try to rename the "lastname" with an "test" , rename the firstname , rename the lastname and delete it later but it didn't work — TR54296, May 11 '18 at 17:50
Can you share what you tried? That would make it easier for someone to help you out. — Hunter McMillen, May 11 '18 at 17:53
Consider a smaller example then. You have two variables: `let a = 5; let b = 10;`. How would you swap the values of `a` and `b`? — Hunter McMillen, May 11 '18 at 17:56
You can apply that same logic using the [`.map()`](https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Array/map) function over your array of employees, except replace `a` with `firstName` and `b` with `lastName` — Hunter McMillen, May 11 '18 at 18:02

Naga Sai A · Answer 1 · 2018-05-11T18:50:51.003

To achieve expected result, use below option of using map

var employees = [{firstName: "Richter", lastName: "Johnas"},


{firstName: "Leibig", lastName: "Linda"},
{firstName: "Schneider", lastName: "Mariane"},
];

employees.map((v,i)=>{
  let fname = v.firstName
  v.firstName = v.lastName
  v.lastName = fname
})
console.log(employees);

code sample - https://codepen.io/nagasai/pen/rvvpwN?editors=1010

Option 2:

Use forEach to achieve expected result and the only difference is that forEach() just return nothing but map() returns an entirely new Array.
For more details, check this link - JavaScript: Difference between .forEach() and .map()

var employees = [{firstName: "Richter", lastName: "Johnas"},


{firstName: "Leibig", lastName: "Linda"},
{firstName: "Schneider", lastName: "Mariane"},
];

employees.forEach((v)=>{
  let fname = v.firstName
  v.firstName = v.lastName
  v.lastName = fname
})
console.log(employees)

You should use forEach if you don't plan on using the array to map returns. — Hunter McMillen, May 11 '18 at 18:14
thanks a lot again, i have read the map function and test it it works perfectly but i will also study the forEach — TR54296, May 11 '18 at 18:23

Change / rename object or exchange content or name

1 Answers1