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JavaScript

Jackie Jen
Jackie Jen
2,723 Points
Posted by Jackie Jen
Jackie Jen
2,723 Points

Problem on storing json object in variable

Hi,

I have install csvtojson npm package https://www.npmjs.com/package/csvtojson. And would like to store my json object into variable so that i can use it outside of the function. Before that i convert my test1.csv file into json format. Then i run my code node index.js, and i get undefined.

Anyone can please help me figure it out what going on. much appreciate

Here is my test1.csv

id,jobtypes,created_at,job_type_ids
1,Full time,09:07.0,3,
2,Full time,59:26.4,3,
3,Permanent,08:35.1,6,
4,Full time,45:55.8,3,
5,Contract,10:17.7,4,
6,Permanent,33:35.1,6,
7,Permanent,59:39.5,6,
8,Permanent,44:13.4,6,
9,Permanent,23:58.9,6,

Below is my code index.js

var Converter = require("csvtojson").Converter;
var converter = new Converter({});
var converterFilter = new Converter({});

function convertTojson (){
    converter.fromFile("./test1.csv",function(err,result){
        if (err){
            console.log(err);
        }else{
            return result;
        }

    });
}
console.log(convertTojson());

2 Answers

alex novickis
alex novickis
34,894 Points
alex novickis
alex novickis
34,894 Points

If you add a return "hello" just before the close of the convertTojson() function, the undefined will go away and be replaced by "hello"

You can test this sort of behavior from the console (or node) by typing in something like

function foo() {}

it will then print "undefined", since that is what the function returns

Other than that - the program does work for me

Jackie Jen
Jackie Jen
2,723 Points
Jackie Jen
Jackie Jen
2,723 Points

Hi,

By just return "hello" it work fine. But how can i return the result. Since it is asynchronous function which mean we don't knw when the converTojson will finish process the result and return it. There for how can i add a call back function in this scenario?

alex novickis
alex novickis
34,894 Points
alex novickis
alex novickis
34,894 Points

I would probably refactor the code so that whatever is using the result is also in the callback function, or something called by the callback function