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

Kosha Burnett
Kosha Burnett
3,340 Points
Posted by Kosha Burnett
Kosha Burnett
3,340 Points

Code Challenge: Accessing All of the Properties in an object. Why am I getting an error?

I'm getting the error message "There was an error with your code: ReferenceError: Strict mode forbids implicit creation of global property 'key'"

I'm having a tough time trying to find what I did wrong. Is there a glitch or am I missing something?

script.js 
var shanghai = {
  population: 14.35e6,
  longitude: '31.2000 N',
  latitude: '121.5000 E',
  country: 'CHN'
};

for (key in shanghai) {
  console.log(shanghai[key]);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Objects</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

Elijah Quesada
.a{fill-rule:evenodd;}techdegree seal-36
Elijah Quesada
Front End Web Development Techdegree Graduate 32,965 Points

You forgot to add the var or let keyword inside the for loop.

Once that is fixed you, will stumble upon another issue. The challenge is asking for the key/property to be logged. Currently, once you add the var/let keyword your loop will print the values.

for (var key in shanghai) {
  console.log(key);
}
Kosha Burnett
Kosha Burnett
3,340 Points
Kosha Burnett
Kosha Burnett
3,340 Points

Thank you! I had a feeling it was something simple like that.