I am trying to get the basic grasp of parsing a CSV file with node js.

I wrote a simple function to get the last character (in my case it is always a number) of every string in an array and show me the biggest number:

var ARRAY_OF_ALL_EMAILS = [email_1, email_22]





function GET_NUMBER() {

    let MAXIMAL_NUMBER;

    for (let i = 0; i < ARRAY_OF_ALL_EMAILS.length; i += 1) {

        if (MAXIMAL_NUMBER == null || MAXIMAL_NUMBER == undefined || MAXIMAL_NUMBER < (ARRAY_OF_ALL_EMAILS[i].slice(-1))) {

            MAXIMAL_NUMBER = (ARRAY_OF_ALL_EMAILS[i].slice(-1))

        }

    }

    return MAXIMAL_NUMBER;

}





let MAXIMAL_NUMBER_FINAL = GET_NUMBER();

console.log(MAXIMAL_NUMBER_FINAL);

this piece of code works as expected:

> node index.js

> 2

However what I am trying to do know is to parse a csv file and extract only col2 of this file and store the values in my variable var ARRAY_OF_ALL_EMAILS; so it behaves as if I declared the array this way: var ARRAY_OF_ALL_EMAILS = [email_1, email_2].

I manage to successfully parse the whole csv file, but when I am trying to use only a certain column I always fail.

Could you please show me how to use only a certain column from a CSV file and store it as an array so I can use it in my GET_NUMBER function? I know it should be possible by either index or name, but it just simply does not work for me.

Example of the csv:

col1,col2,col3,col4

aaa1,aaa_1,aaa3,aaa4

bbb1,bbb_2,bbb3,bbb4

ccc1,ccc_3,ccc3,ccc4

For this I am using a csv package (npm install csv)

Thanks

Edit

With Barkaas help I have this:

const parse = require('csv-parse/lib/sync'); //include

const fs = require(fs);



//loading data from the file

var global_data = fs.readFileSync(data.csv).toString();



//the dataset

const input = global_data;



//calling the npm package and save to records

const records = parse(input, {

  columns: true,

  skip_empty_lines: true

});



//map the output from csv-parse to the column

const column_two = records.map(rec => rec[col2]);



//assing the values to another variable used in my function

var ARRAY_OF_ALL_EMAILS = column_two//[aaa_1, bbb_4444444, ccc_3333333]



//function to return the highest number in every string

function GET_NUMBER() {

    let MAXIMAL_NUMBER;

    for (let i = 0; i < ARRAY_OF_ALL_EMAILS.length; i += 1) {

        let n = ARRAY_OF_ALL_EMAILS[i].lastIndexOf('_');

        let result = ARRAY_OF_ALL_EMAILS[i].substring(n + 1);

        if (MAXIMAL_NUMBER == null || MAXIMAL_NUMBER == undefined || MAXIMAL_NUMBER < result) {

            MAXIMAL_NUMBER = result

        }

    }

    return MAXIMAL_NUMBER;

}



//print the highest number from every string

let MAXIMAL_NUMBER_FINAL = GET_NUMBER();

console.log(MAXIMAL_NUMBER_FINAL);

This works for me.