Javascript- return an object from a function

Question

I am trying to get a function that prompts a user for info and then passes that info to an object. So far it does not seem to be doing that.

// my object constructor
var Person = function (firstName, lastName, areaCode, phone) {
  this.firstName = firstName;
  this.lastName = lastName;
  this.areaCode = areaCode;
  this.phone = phone;
}

// my function to get user info
function getInfo() {
  firstName = prompt("What is your first name: ");
  lastName = prompt("What is your last name: ");
  areaCode = prompt("What is your area code: ");
  phone = prompt("What is your phone number: ");
  var guy = Person(firstName, lastName, areaCode, phone);
  return guy;
}

// calling the function
getInfo();

// test to see if it actually worked
document.writeln(guy.firstName);

you are missing "new" var guy = new Person(firstName, lastName, areaCode, phone); — Prabhu Murthy
– Prabhu Murthy, Commented Sep 21, 2014 at 15:57

Oriol · Accepted Answer · 2014-09-21 16:16:01Z

4

Your code had three problems:

When you instantiate a constructor, you must use new.
If you declare a variable (guy) inside a function, it won't be accessible from the outside. You can
- Declare it outside, and set its value inside the function.
- Return it to the outside. In this case you must use the return value.
You didn't define variables inside getInfo. Then, it will only work in non strict mode, and they will become globals, which may be bad.

// my object constructor
var Person = function (firstName, lastName, areaCode, phone) {
  this.firstName = firstName;
  this.lastName = lastName;
  this.areaCode = areaCode;
  this.phone = phone;
}

// my function to get user info
function getInfo() {
  var firstName = prompt("What is your first name: "),
      lastName = prompt("What is your last name: "),
      areaCode = prompt("What is your area code: "),
      phone = prompt("What is your phone number: ");
  return new Person(firstName, lastName, areaCode, phone);
}

// calling the function
var guy = getInfo();

// test to see if it actually worked
document.writeln(guy.firstName);

edited Sep 21, 2014 at 16:16

answered Sep 21, 2014 at 16:02

Oriol

291k71 gold badges458 silver badges535 bronze badges

Sign up to request clarification or add additional context in comments.

7 Comments

Shai Over a year ago

Missing var for the four variables in getInfo, don't want them using outer scope

bmceldowney Over a year ago

problem 4, not using the return value of getInfo()

Shai Over a year ago

@Oriol getting there – now the first two are local... ;-)

Oriol Over a year ago

@bmceldowney I think OP didn't use the return value because he thought that defining guy inside getInfo made it available outside too.

bmceldowney Over a year ago

Seems possible, but considering the title of the question is about returning an object from a function, it might be worthwhile to point out that he's returning the object correctly but he's just not doing anything with it.

|

Collectives™ on Stack Overflow

Javascript- return an object from a function

1 Answer 1

7 Comments

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

7 Comments

Related