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JavaScript JavaScript Loops, Arrays and Objects Tracking Data Using Objects The Student Record Search Challenge Solution

Posted by German Iakovlev
German Iakovlev
5,506 Points

Using students.indexOf(search) for the challenge

I have been trying to use the array.indexOf method to go to the specific student from the students array. But somehow the studentID has always a value of -1. And it causes the following error Uncaught TypeError: Cannot read property 'name' of undefined(…) on this line:

studentList += '<h2>Student: ' + students[studentID].name + '</h2>'; 

function print(HTML) {
  document.getElementById('output').innerHTML = HTML;
};

var studentList = '';

while (true) {
  var search= prompt('give student name you want to look up');
  //Use the student name for getting the index of the student in the array
  var studentID = students.indexOf(search);
  console.log(studentID);

    studentList += '<h2>Student: ' + students[studentID].name + '</h2>';
    studentList += 'Track' + ': ' + students[studentID].track + '<br>';  
    studentList += 'Achievements: ' + students[studentID].achievement + '<br>';
    studentList += 'Points: ' + students[studentID].achievement + '<br><br>';

  print(studentList);
};

Would be awesome if someone could tell me where it went wrong :) Thanks a lot!

1 Answer

Ryan Zimmerman
Ryan Zimmerman
3,854 Points
Ryan Zimmerman
Ryan Zimmerman
3,854 Points

So you have an array of objects. The indexOf will only work on the array. So if it was just an array of numbers that would work. Use a "forEach" and pass it a "for in loop" that will look at each object.

German Iakovlev
German Iakovlev
5,506 Points

Thank you for the heads up, Ryan!

Will look into that.