CODEWITHSUNDEEP
javascriptjqueryarrayssplittext-files
Tiago
Tiago

Reputation: 4480

JavaScript split() method resulting in undefined

I'm working on a simple program that will select a random string from an array.

I started with a predefined array, but about halfway through wondered if it wouldn't be simpler (or more elegant) to use a text file (.txt), since I have a bit over 1000 items.

I found this solution here (for which I take no credit) and it is working for me...

function readTextFile(file) {
    var items = [];
    var rawFile = new XMLHttpRequest();
    rawFile.open("GET", file, true);
    rawFile.onreadystatechange = function() {
        if(rawFile.readyState === 4)
        {
            if(rawFile.status === 200 || rawFile.status === 0)
            {
                var items = rawFile.responseText.split('\n');
                alert(items[0]);
            }
        }
    };
    rawFile.send(null);
}

readTextFile('source.txt');

...to an extent.

I want the array items[] to contain one line per item. In other words I want to split per new line. However, all array items are undefiend after items[0] when I use split('\n').

items[0] in the example above becomes the first sentence, so that much is correct. If I want to alert items[1] I get undefined.

If I use some other split point, such as split(''), it works correctly, separating each character per item ONLY until the line breaks, after which point I get undefined again.

Let's say the first line of the .txt is "asd": so 'asd' is defined in array as :

items[0] = 'a'
items[1] = 's'
items[2] = 'd'
items[3] = undefined

This is what I would get. Where am I wrong?

Contents of text file:

asfe
asdasdasd
asdasd

fgfg

Upvotes: 8

Views: 26494

Answers (3)

Leonardo Moreno
Leonardo Moreno

Reputation: 172

Try adding a String cast:

var items = String(rawFile.responseText).split('\n');

Upvotes: 6

Shadow Wizard
Shadow Wizard

Reputation: 66388

After some messing around with this I believe the problem is with your text editor that save the file with line breaks consisting of \r instead of \n, maybe Unix based server?

Anyway, you can replace those and it should work:

var rawText = rawFile.responseText;
rawText = rawText.replace(/\r\n/g, "\n");
rawText = rawText.replace(/\n\r/g, "\n");
rawText = rawText.replace(/\r/g, "\n");
var items = rawText.split('\n');

Upvotes: 2

BenM
BenM

Reputation: 53208

Probably because there's a blank row at the end of the responseText. Try using trim():

var items = rawFile.responseText.trim().split('\n');

Upvotes: 0

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