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

Colin Sygiel
Colin Sygiel
5,249 Points
Posted by Colin Sygiel
Colin Sygiel
5,249 Points

I am very close, but something is not working. Please have a looksy!

I am getting an error with line 45: students.js:45 Uncaught ReferenceError: message is not defined(…) This is the line towards the bottom with the <h2> tag but I can't figure out why it's acting up.

/*Accessible information about students - loops, arrays and objects*/

//Group of 5 students (objects) containing name, track, achievements and points
var students = [
{
name: 'Colin',
track: 'vr',
achievements: 100,
points: 34
},
{
name: 'Vira',
track: 'iOS',
achievements: 90,
points: 98
},
{
name: 'Zara',
track: 'android',
achievements: 871,
points: 129
},
{
name: 'Peach',
track: 'web',
achievements: 42,
points: 12
},
{
name: 'Lee',
track: 'ai',
achievements: 900,
points: 123
}
];

//function for printing a message anywhere on the webpage
function print(message) {
var outputDiv = document.getElementById('output');
outputDiv.innerHTML = message;
}

//loop for crawling array and printing properties to screen
for (i = 0; i < students.length; i += 1) {
message += '<h2>Student: ' + students[i].name + '</h2>';
message += '<p>Track: ' + students[i].track + '</p>';
message += '<p>Achievements: ' + students[i].achievements + '</p>';
message += '<p>Points: ' + students[i].points + '</p>';
}

print(message);
Colin Sygiel
Colin Sygiel
5,249 Points
Colin Sygiel
Colin Sygiel
5,249 Points

I solved it! Looks like I forgot to declare the message as a variable :)

1 Answer

Jason Cook
Jason Cook
11,403 Points
Jason Cook
Jason Cook
11,403 Points

I see you solved it already, nice job! By the way, I have an alternative version of that bottom functionality you might like to plugin and try (just for experimenting). It dynamically loops through using a nested loop, programmatically, determining the property names.

If you're a code geek like me, you might appreciate it, so here it is (the top array of objects can stay the same - just replace from the print() function down with this alternate version to try).

I know it's not as readable, for maintainability, but it's just for fun and learning purposes :-)

function print (message) {
  var outputDiv = document.getElementById("output");
  outputDiv.innerHTML = message;
}

var studentList = '';

//Dynamically loop through the array
for(var i = 0; i < students.length; i++) {
  for (key in students[i]) {
    if (key === "name") {
      studentList += '<p class="studentname">' + students[i][key] + '</h2>';
    } else {
      studentList += '<p>' + students[i][key] + '</p>';
    }
  }
  studentList += '<br>';
}

print(studentList);

Happy coding! :-)

Colin Sygiel
Colin Sygiel
5,249 Points
Colin Sygiel
Colin Sygiel
5,249 Points

Thanks so much Jason - this is very cool and I appreciate your efforts and enthusiasm. Happy coding to you too :)