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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Iterating through an Array

Posted by Erik Wells
Erik Wells
5,403 Points

Iterating through an array Challenge Task

I am having trouble logging the contents of my array. My code will log the index numbers but not the numbers they are in the array. Can anyone help?

script.js 
var temperatures = [100,90,99,80,70,65,30,10];

for ( var i = 0; i < temperatures.length; i += 1) {
    console.log(i);
}
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>

1 Answer

moonshine
moonshine
8,449 Points

You should log the array item at the index instead of the index itself.

var temperatures = [100,90,99,80,70,65,30,10];

for ( var i = 0; i < temperatures.length; i += 1) {
    console.log(temperatures[i]);
}
Kevin Lozandier
Kevin Lozandier
Courses Plus Student 53,747 Points

Floris Creyf is correct; you can also use a .forEach loop which will become invaluable for you to use in asynchronous situations (i.e. consuming events as streams):

let temperatures = [100, 90, 99, 80, 70, 65, 30, 10]; 
temperatures.forEach(function(temperature){
  console.log(temperature);
});

You can also use a of loop, which is also more concise more ideal for looping NodeLists & items within your own defined objects that you define as being enumerable (both being ES6 concepts):

let temperatures = [100, 90, 99, 80, 70, 65, 30, 10]; 
for (temperature of temperatures) {
  console.log(temperature);
}
Erik Wells
Erik Wells
5,403 Points

Thank You Floris!