Return global array element

Question

I am trying to simply print out a global array list of students that I have imported from a csv file. I've done enough troubleshooting to know that the data is being imported and read fine. The common answer seems to be that you don't require a "var" declaration for a global array but this wasn't working for me either.

Here is my declaration:

//Student array list from csv import
 studentList = []; 
//window.studentList = [];

This is where I initialize the array:

function processData(csv){
let allLines = csv.split(/\r\n|\n/); 

for(let i = 0; i < allLines.length; i++)
{
    let row = allLines[i].split(",");
    let col = []; 

    for(let j = 0; j < row.length; j++)
    {
       col.push(row[j]);  
    }
    if(col == " ") break;
    studentList.push(col);
}

//when I alert the array element by element the data is being read from within this function 
for(let i =0; i < studentList.length; i++)
{
    alert(studentList[i]);
}
}

But if I was to use a get method to return the elements I would get an 'undefined' error

function getStudent(index) {
     return studentList[index];
}

for(let i = 0; i < studentList.length; i++)
{
      alert(getStudent[i]);
}

EDIT: Despite that solution being right, I still have the same issue when calling from another function. For example in the following I need to return the trip departure for each student which is undefined.

function getStudentsDeparture(i)  
{
    trip.departure = getStudent(i);
    alert(trip.departure);          //prints undefined

    trip.destination = "123 Smith Rd, Maddingley VIC 3340"; 
    console.log('dest is: ' + trip.destination + ' dept is: ' + 
    trip.departure);
 }

Trunst · Accepted Answer · 2018-11-26 07:52:30Z

3

The issue seems to be that you try to get an index from the function getStudent[i]. Try change that row to alert(getStudent(i)); with parenthesis.

EDIT I tested with this code and it works fine for me

studentList = [];

studentList.push('student1');

function getStudent(index) {
    return studentList[index];
}

function getStudentsDeparture(i) {
    var student = getStudent(i);
    alert(student);
}

getStudentsDeparture(0);

edited Nov 26, 2018 at 7:52

answered Nov 23, 2018 at 14:33

Trunst

8747 silver badges8 bronze badges

Sign up to request clarification or add additional context in comments.

2 Comments

Stefan Over a year ago

You are right, but when still when I try from a separate function I am still getting undefined.

Trunst Over a year ago

@Stefan Are you sure that the index is within range of studentList array?

Collectives™ on Stack Overflow

Return global array element

1 Answer 1

2 Comments

Your Answer

Hot Network Questions

Collectives™ on Stack Overflow

1 Answer 1

2 Comments

Your Answer

Sign up or log in

Post as a guest

Related