A basic question/problem with array element as undefined

Question

Hello everybody,
thank you for looking at my problem. I'm very new to scripting and javaScript and I've encountered a strange problem. I'm always trying to solve all my problem myself, with documentation (it help to learn) or in the last instance with help of google. But in this case I am stuck. I'm sure its something very simple and elementary.
Here I have a code which simply loads a text file (txt), loads the content of the file in to a "var content". This text file contents a font family name, each name on a separate line, like:
Albertus
Antenna
Antique
Arial
Arimo
Avant
Barber1
Barber2
Barber3
Barber4
Birch
Blackoak ...etc
Now, I loop trough the content variable, extract each letter and add it to the "fontList[i]" array. If the character is a line break the fontList[i] array adds another element (i = i + 1); That's how I separate every single name into its own array element;
The problem which I am having is, when I loop trough the fontList array and $.writeln(fontList[i]) the result in the console is:
undefinedAlbertus
undefinedAntenna
undefinedAntique
undefinedArial ...etc.
I seriously don't get it, where the undefined is coming from? As far as I have tested each digit being added into the array element, I can't see anything out of ordinary.
Here is my code:
#target illustrator
var doc = app.documents.add();
//open file
var myFile = new File ("c:/ScriptFiles/installedFonts-Families.txt");
var openFile = myFile.open("r");
//check if open
if(openFile == true){
    $.writeln("The file has loaded")}
else {$.writeln("The file did not load, check the name or the path");}
//load the file content into a variable
var content = myFile.read();
myFile.close();
var ch;
var x = 0;
var fontList = [];
for (var i = 0; i < content.length; i++) {
    ch = content.charAt (i);
        if((ch) !== (String.fromCharCode(10))) {
            fontList[x] += ch;
        else {
            x ++;
for ( i = 0; i < fontList.length; i++) {
   $.writeln(fontList[i]);
doc.close (SaveOptions.DONOTSAVECHANGES);
Thank you for any help or explanation. If you have any advice on how to improve my practices or any hint, please feel free to say. Thank you

Answer 1

CarlosCantos wrote an amazing script a while back (2013) that may help you in your endeavor. Below is his code, I had nothing to do with this other then give him praise and I hope it doesn't offend him since it was pasted on the forums here.
This has helped me do something similar to what your doing.
Thanks again CarlosCanto
// script.name = fontList.jsx;
// script.description = creates a document and makes a list of all fonts seen by Illustrator;
// script.requirements = none; // runs on CS4 and newer;
// script.parent = CarlosCanto // 02/17/2013;
// script.elegant = false;
#target illustrator
var edgeSpacing = 10;
var columnSpacing = 195;
var docPreset = new DocumentPreset;
docPreset.width = 800;
docPreset.height = 600;
var idoc = documents.addDocument(DocumentColorSpace.CMYK, docPreset);
var x = edgeSpacing;
var yyy = (idoc.height - edgeSpacing);
var fontCount = textFonts.length;
var col = 1;
var ABcount = 1;
for(var i=0; i<fontCount; i++) {
    sFontName = textFonts[i].name;
    var itext = idoc.textFrames.add();
    itext.textRange.characterAttributes.size = 12;
    itext.contents = sFontName;
    //$.writeln(yyy);
    itext.top = yyy;
    itext.left = x;
    itext.textRange.characterAttributes.textFont = textFonts.getByName(textFonts[i].name);
    // check wether the text frame will go off the bottom edge of the document
    if( (yyy-=(itext.height)) <= 20 ) {
        yyy = (idoc.height - edgeSpacing);
        x += columnSpacing;
        col++;
        if (col>4) {
            var ab = idoc.artboards[ABcount-1].artboardRect;
            var abtop = ab[1];
            var ableft = ab[0];
            var abright = ab[2];
            var abbottom = ab[3];
            var ntop = abtop;
            var nleft = abright+edgeSpacing;
            var nbottom = abbottom;
            var nright = abright-ableft+nleft;
            var abRect = [nleft, ntop, nright, nbottom];
            var newAb = idoc.artboards.add(abRect);
            x = nleft+edgeSpacing;
            ABcount++;
            col=1;
    //else yyy-=(itext.height);