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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Build an Object Challenge, Part 2

Michele Adami
Michele Adami
5,691 Points
Posted by Michele Adami
Michele Adami
5,691 Points

This is my version... a little more complicated

The main difference from the original is that i used an array as a data type in the track property. I also used the for in loop to print out the properties' value.

var students = [
  {
    name: 'Michele',
    tracks: ['HTML', 'CSS', 'JavaScript'],
    achievment: 56,
    points: 3000
  },
  {
    name: 'Orazio',
    tracks: ['PHP', 'Ruby', 'Developer Tools', 'Java'],
    achievment: 275,
    points: 14562
  },
  {
    name: 'Natalia',
    tracks: ['Design', 'Business'],
    achievment: 12,
    points: 1206
  },
  {
    name: 'Pietro',
    tracks: ['HTML', 'CSS', 'JavaScript', 'PHP', 'Python', 'Perl', 'Ruby', 'Java', 'Game Development', 'Developer Tools'],
    achievment: 2752,
    points: 123763
  },
  {
    name: 'Gianni',
    tracks: ['HTML', 'CSS'],
    achievment: 5,
    points: 576
  }
];

var thing = document.getElementById('output');

for(var i = 0; i < students.length; i++){
  thing.innerHTML += '<h2>' + students[i]['name'] + '</h2><ol>';

  for(var prop in students[i]){
    if(students[i][prop] === students[i]['name']) continue;
    if(typeof students[i][prop] === 'object') students[i][prop] = students[i][prop].join(', ');
    thing.innerHTML+= '<li>' + students[i][prop] + '</li>';
  }
  thing.innerHTML+='</ol>';
}
Gunhoo Yoon
Gunhoo Yoon
5,027 Points
Gunhoo Yoon
Gunhoo Yoon
5,027 Points

if(students[i][prop] === students[i]['name']) continue; Why not remove this line?

typeof students[i][prop] === 'object' is considered not so good practice since null, array-like object and object is considered type of object. If you want to check for an array use Array.isArray(), isinstanceof, tostring etc... You can find more on Google with keyword: javascript array checking.

Michele Adami
Michele Adami
5,691 Points
Michele Adami
Michele Adami
5,691 Points

Thank you for the advice about the typeof, i didn't know about the existence of the isArray method.

if(students[i][prop] === students[i]['name']) continue; Why not remove this line?

Because I want that the name property of the objects should be printed out in a h2 tag and not in a li tag like the other properties. So i told the for in loop to bypass that property.

Gunhoo Yoon
Gunhoo Yoon
5,027 Points
Gunhoo Yoon
Gunhoo Yoon
5,027 Points

Oh I see great I missed that part.