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

Object Challenge part II

Noticed some differences in our code but still the same output. I did not separate my programming from my student objects either but I understand the good organization practice behind doing that. I was just wondering why use a 'student var; ' from the video and a for loop instead of a for in loop?

var students = [ 
  { 
    name: 'Dave',
    track: 'Front End Development',
    achievements: 158,
    points: 14730
  },
  {
    name: 'Jody',
    track: 'iOS Development with Swift',
    achievements: '175',
    points: '16375'
  },
  {
    name: 'Jordan',
    track: 'PHP Development',
    achievements: '55',
    points: '2025'
  },
  {
    name: 'John',
    track: 'Learn WordPress',
    achievements: '40',
    points: '1950'
  },
  {
    name: 'Trish',
    track: 'Rails Development',
    achievements: '5',
    points: '350'
  }
];

function print(message) {
  var div = document.getElementById('output');
  div.innerHTML = message;
}

var html = '';

for (student in students) {
  html += '<h2>Student: ' + students[student].name + '</h2>';
  html += '<p>Track: ' + students[student].track + '</p>';
  html += '<p>Points: ' + students[student].points + '</p>';
  html += '<p>Achievements: '+ students[student].achievements + '</p>';
}

print(html);

1 Answer

Steven Parker
Steven Parker
216,057 Points

The student var with the conventional for loop allows for more concise property access. But you could get the benefits of both versions by using of instead of in:

for (student of students)
  html += '<h2>Student: ' + student.name + '</h2>'
        + '<p>Track: ' + student.track + '</p>'
        + '<p>Points: ' + student.points + '</p>'
        + '<p>Achievements: ' + student.achievements + '</p>';

(I streamlined it a bit further by making the loop just one statement)