Basic Data Structures - Check if an Object has a Property

JavaScript
1

Hi! I solved this challenge and I understand how the “in” keyword works; however I was just wondering why I had to write their names as strings, even though they are not strings in the object? Thanks!

Your code so far

let users = {
  Alan: {
    age: 27,
    online: true
  },
  Jeff: {
    age: 32,
    online: true
  },
  Sarah: {
    age: 48,
    online: true
  },
  Ryan: {
    age: 19,
    online: true
  }
};

function isEveryoneHere(userObj) {
  // Only change code below this line
return "Alan" in userObj && "Jeff" in userObj && "Sarah" in userObj && "Ryan" in userObj
  // Only change code above this line
}

console.log(isEveryoneHere(users));

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36

Challenge: Basic Data Structures - Check if an Object has a Property

Link to the challenge:

2

Object keys are always strings. The object literal syntax is a shortcut that skips the quotation marks in the key names.

3

Oh interesting, thank you so much! I never knew that

1 Like
4

This topic was automatically closed 182 days after the last reply. New replies are no longer allowed.