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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects Accessing All of the Properties in an Object

for in loops

Can someone explain why this for in loop is not working?

script.js
var shanghai = {
  population: 14.35e6,
  longitude: '31.2000 N',
  latitude: '121.5000 E',
  country: 'CHN'
};
for (var country in shanghai){
    console.log(country); 
}
for (prop in shanghai){
    console.log(prop, ': ', shanghai[prop]);
}
index.html
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

2 Answers

Neil McPartlin
Neil McPartlin
14,662 Points

Hi Conary.

Can someone explain why this for in loop is not working?

Yes. You will have passed Challenge 1 with your code...

for (var country in shanghai){
    console.log(country); 
}

You used the string 'country' which does look confusing (rather than 'prop' or some other label), but it's just a label and you met the criteria set out in Challenge 1.

Challenge 2 states...

Now that you are logging out the property names, include the property values too...

So the implication here is that they just want you to edit the code you already provided, rather than add a second 'for in' loop. So just edit your answer to Challenge 1 like so...

for (var country in shanghai){
    console.log(country, ': ', shanghai[country]); 
}

Thank you Neil. That was helpful.