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

Posted by Kim Dallas
Kim Dallas
11,461 Points

this one is totally confusing

shangai is the property but there is no value for it?

script.js 
var shanghai = {
  population: 14.35e6,
  longitude: '31.2000 N',
  latitude: '121.5000 E',
  country: 'CHN'
};for (var something in shanghai){
    console.log(something + ': ' + shanghai[something]);
}for (var population in shanghai){
    console.log(something + ': ' + shanghai[something]);
}
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

Christian Bartram
Christian Bartram
1,193 Points
Christian Bartram
Christian Bartram
1,193 Points

shanghaiis the variable which hold properties of the shanghai object (lat, long, country, population). So you can access the properties of the shanghai object individually using:

shanghai.country; // CHN
// or
shanghai['country'] // CHN

All you are doing is using a for/in loop to iterate over all the properties of the object. So:

var something 
// is referring to the strings: population, latitude, longitude, country
// and 
shanghai[something] 
// is equal to
shanghai.population
// then
shanghai.latitude
//then
shanghai.longitude
...etc