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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Build an Object Challenge, Part 1

Samantha Atkinson
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Samantha Atkinson
Front End Web Development Techdegree Graduate 40,307 Points
Posted by Samantha Atkinson
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Samantha Atkinson
Front End Web Development Techdegree Graduate 40,307 Points

I don't understand why when I print to my doc the first student has: underfinedStudent 1.

var student = [

{ studentNo: 1, name: "Janet Ray", track: "iOS", achievements: 50, points: 10345 },

{ studentNo: 2, name: "Rudy Modeste", track: "Wordpress", achievements: 35, points: 7678 },

{ studentNo: 3, name: "Louise Right", track: "Front End Web Development", achievements: 75, points: 15123 },
{ studentNo: 4,
name: "Cathy Kendo", track: "Web Design", achievements: 40, points: 9987 },

{ studentNo: 5, name: "Matt Atkinson", track: "Java Web Development", achievements: 80, points: 20764 }

];

var stuPerson; var html;

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

           for ( var i= 0; i < student.length; i+= 1){
             stuPerson  ="Student: " + student[i].studentNo + "<br>";
             stuPerson  +="Name: " + student[i].name + "<br>";
             stuPerson +="Track: " + student[i].track + "<br>";
             stuPerson +="Achievements: " + student[i].achievements + "<br>";
             stuPerson += "Points: " + student[i].points +"<br><br>";
             html += stuPerson;


            }

//5 Print out all student info

print(html); '''

2 Answers

Austin Britton
Austin Britton
6,531 Points
Austin Britton
Austin Britton
6,531 Points

It has to do with the fact that when your declared 'var html' you didn't define it and where its being addressed from inside the function. I think your tacking the student information onto the end of the 'undefined' value inside 'html' from when you declared it. Two ways to solve off the top of my head

If you set it equal to an empty string when you declare it, you'll find yourself without an undefined student!

or you can make your loop a function, create a local object, return that to a variable and pass it off to your print function where message will no longer be undefined

Hope this helps!