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

Posted by Angelic Thomason
Angelic Thomason
1,889 Points

Should I use a while instead?

Would a for loop or a while loop be better?

script.js 
var temperatures = [100,99,90,80,70,65,30,10];
for (var i = 0; i < temperatures.lengh; i = 1); {
  console.log(temperatures[i]);
  }
index.html 
<!DOCTYPE html>
<html>
<head>
  <meta charset="utf-8">
  <title>JavaScript Loops</title>
</head>
<body>
<script src="script.js"></script>
</body>
</html>
Devin Thomas
Devin Thomas
2,935 Points
Devin Thomas
Devin Thomas
2,935 Points

You did everything correct. You want your last statement to increment through each iteration and remove the semi-colon before the open bracket.

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

for(var i =0; i < temperatures.length; i++){
console.log(temperatures[i]);
}

2 Answers

Owen McComas
Owen McComas
8,472 Points

You can use either and they will both work perfectly well. That being said, people tend to use for loops quite a bit more often than while loops or do-while loops in the real world. Looking at your for loop, there are a few minor things that will make it so it doesn't work.

  1. It looks like you just misspelled length in 'temperature.length'
  2. There shouldn't be a semi-colon at the end of the parenthesis there in the first part of the for-loop.
  3. You need to specify the iteration declaration. "i = 1" should be i++ or i += 1. This tells the loop to add 1 to the index value each loop.

Your for loop should look something like this. 

var temperatures = [100,99,90,80,70,65,30,10];
for (var i = 0; i < temperatures.length; i++ ) {
  console.log(temperatures[i]);
  }
Angelic Thomason
Angelic Thomason
1,889 Points
Angelic Thomason
Angelic Thomason
1,889 Points

Ok I see now, it's starting to come a little easier now