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So I have to parse files that are in differents directories in js and in order to do that I use a for in loop to get the data from each file. At each iteration of my loop I run fs.Readfile and then I attribute the values for the file currently being treated. But the console.log shows that I is always equals to 1 in the for loop and that data[i] is not being assigned the right values for fn, ln and dob.

This code :

var fs = require('fs');
var path = require('path');
var data = [];
var directories = fs.readdirSync('./path/to/')
    .filter(file => fs.lstatSync(path.join('./path/to/', file)).isDirectory());
var fn = "";
var ln = "";
var dob = "";
var strArray;

for (var i in directories)
{
    fs.readFile('./path/to/' + directories[i] + '/file.html', 'utf8', function (err, content)
    {
        if (err)
            return console.log(err);
        strArray = content.split(/([A-Z][a-z]*) ([A-Z][a-z]*) ([0-9]{2}\/[0-9]{2}\/[0-9]{4})/g);
        fn = strArray[1];
        ln = strArray[2];
        dob = strArray[3];
        console.log(fn, ln, dob, i);
    });
    console.log(i);
    data[i] =   {       
                    id:directories[i],
                    fn:fn,
                    ln:ln,
                    dob:dob };
}
console.log(data);

Produce this output :

0
1
[ { id: '7X123Y23', fn: '', ln: '', dob: '' },
  { id: '7X423Y33', fn: '', ln: '', dob: '' } ]
Jean Martin 23/04/1968 1
Jeanne Martine 17/10/1972 1

Which feels pretty unlogical for me about both the content displayed and the order in which elements are displayed.

Edit

I saw the other question before, it didn't seems to work before but now i is prompted 0 then 1 when console.log(fn, ln, dob, i); is ran, but even with this working fine now, data[i] is not attributed the right values.

The new output :

0
1
[ { id: '7X123Y23', fn: '', ln: '', dob: '' },
  { id: '7X423Y33', fn: '', ln: '', dob: '' } ]
Jean Martin 23/04/1968 0
Jeanne Martine 17/10/1972 1

I've tried to change var to let for fn, ln, dob and strArray but it doesn't change anything. I come from C and I'm pretty new to js and OOP and the variable scope thing is really something I don't get.

To clarify the question, how do I get data to have this value ? :

[ { id: '7X123Y23', fn: 'Jean', ln: 'Martin', dob: '23/04/1968' },
  { id: '7X423Y33', fn: 'Jeanne', ln: 'Martine', dob: '17/10/1972' } ]
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Gaëtan Brochard
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  • Use `let` instead of `var` in `for (var i in directories)`. And why would you use `for...in` on arrays. `forEach` would solve the problem: `directories.forEach(function(dir, index) { ... });`. – ibrahim mahrir Jul 07 '17 at 10:40
  • As well as the link in the first comment, you should probably also see [Why is my variable unaltered after I modify it inside of a function? - Asynchronous code reference](http://stackoverflow.com/questions/23667086/why-is-my-variable-unaltered-after-i-modify-it-inside-of-a-function-asynchron) – James Thorpe Jul 07 '17 at 10:42
  • I'm gonna use forEach, thanks to ibrahim, gonna read the stuff on variable too, I'm new to stack overflow do I need to close the topic as it looks like a duplicate and that the answer was given in commentary anyway ? – Gaëtan Brochard Jul 07 '17 at 10:55

0 Answers0