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

Posted by ammarkhan
.a{fill-rule:evenodd;}techdegree
ammarkhan
Front End Web Development Techdegree Student 21,661 Points

Accessing objects

While my code work fine, but if i have something like this javascript Track:"Web Design, Front End , JS" it output <b>undefined<b> I am accessing it as 

for (var i = 0; i< students.length; i++){
    student = students[i];
    //document.write(student);
    //message = "<h4>Student Name : "+ student.Name + "</h4>";
    message = "<p> " + student.Tracks + "</p>";
    document.write(message);
}```

and my student.js is as follow
```javascript
var students = [
    {
        Name:"a",
        Track:"Web Design, Front End , JS",
        Achievements:11000,
        points:"More than 10k"
    },
    {
        Name:"b",
        Track:"iOS",
        Achievements:"Marv",
        points:"Starting"
    },
    {
        Name:"c",
        Tracks:"VR",
        Achievements:"Getting started",
        points:"0"
    },
    {
        Name:"d",
        Tracks:"None",
        Achievements:0,
        points:"Starting"
    }
]

1 Answer

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

:point_right: Are you using the same property names as defined in student.js?

You didn't show that part of your code, but unless you deviated from the video, the property names you are using are not part of the student object.

Your code above is attempting to access student.Tracks (plural, and capital "T"), but the video uses student.track (singular, lower-case "t").

"What's in your wallet student.js?" :point_left: Joke based on American TV, in case you're from elsewhere and not familiar

ammarkhan
.a{fill-rule:evenodd;}techdegree
ammarkhan
Front End Web Development Techdegree Student 21,661 Points

Steven Parker sorry for not posting the other filer. I have updated my question. Have a look now.

Steven Parker
Steven Parker
231,269 Points
Steven Parker
Steven Parker
231,269 Points

Aha - here's the cause :point_right: The propery names in student.js are not consistent.

The first two items have a property named "Track" (singular), and the last two have a property named "Tracks" (plural).

Your code is looking for student.Tracks, which will be undefined in the first two items.