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JavaScript JavaScript Loops, Arrays and Objects Tracking Multiple Items with Arrays Two-Dimensional Arrays

Oliver Sewell
Oliver Sewell
16,425 Points
Posted by Oliver Sewell
Oliver Sewell
16,425 Points

I have decided to do the code this way i was wondering if theirs anything wrong/bad about it as its different to the vid

var studentScores = [
['oliver' , 10],
['tom' , 20],
['craig', 38],
['emma', 15]
];


function listScores() {
  var listHtml = '<ol>';
  for(var i = 0; i < studentScores.length; i+=1) {
  listHtml += '<li>' + studentScores[i][0] + ' got ' + studentScores[i][1];
  } 
  listHtml += '</ol>';
  document.write(listHtml);
}

listScores(studentScores);
nico dev
nico dev
20,364 Points
nico dev
nico dev
20,364 Points

Hi Oliver,

I know it's late, but just in case, don't forget to close each <li> tag. You do that just adding " + '</li>' " after the "studentScores[i][1]".

1 Answer

Kevin Goudswaard
Kevin Goudswaard
11,061 Points
Kevin Goudswaard
Kevin Goudswaard
11,061 Points

The only thing I can really see with this is that you have many instances where you're adding on to your listHtml variable. It took me a second to find out what it was doing, and when I did it made sense. So basically by virtue of your design, you are making future developers "crack" your code, which is intrinsically a bad practice. I fiddled with it for a while, and I'll admit it challenged me! But I re-wrote it using dot notation which is no better in essence to what you wrote except its a little more straightforward. Here is the code rewritten that way:

var studentScores = [
['oliver', 10],
['tom', 20],
['craig', 38],
['emma', 15]
];

var list = [];
var element = document.getElementById("mylist");

function listScores() { 
  for (var i = 0; i < studentScores.length; i++) {
  list += studentScores[i][0] + ' got ' + studentScores[i][1] + "<br></br>";
  }
  element.innerHTML = list;
}

listScores();

This includes an html document with a H1 element with the ID = "myList"

Thoughts? better? worse? :)

Kevin

Oliver Sewell
Oliver Sewell
16,425 Points
Oliver Sewell
Oliver Sewell
16,425 Points

thanks for the answer kevin , im not too sure :) im abit of a newb when it comes to javascript so i'm just practicing