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Scroll text method, works with arrays, not with string

Basic javascript function to scroll the text in the title bar, I'm calling it via a setInterval("rotateTitle()", 1000); call after onload.
This function, which takes text from an array, works perfectly.
var counter = 0;
function rotateTitle() {
var baseTitle = "www.mydomain.com - now with JavaScript";
var titleArray = new Array("a","b","c","d","e","f","g");
var titleString = "abcdefg";
var scrollText = getNextScroll(titleArray);
window.document.title=baseTitle.concat(scrollText);
}
function getNextScroll(inValue) {
var str = " ";
for (var i = 0; i<inValue.length; i++) {
var index = i+counter;
if (i+counter >= inValue.length) {
index -= inValue.length;
}
str += inValue[index];
}
counter++;
if (counter > inValue.length) {
counter = 0;
}
return str;
}
Edited here for clarity:
Now if I rewrite the function to scroll a string (not an array), I change the line
str += inValue[index];
to
str.concat(inValue.charAt(index));
and change getNextScroll(titleArray) to getNextScroll(titleString), the script seems to execute, but only the baseTitle is shown.
Why is this wrong?

You have to assign the result of str.concat back to str; otherwise you'll miss the concat operation. Instead of charAt you must use inValue[index].
Do like this:
str = str.concat(inValue[index]);
Here's a JS Bin: http://jsbin.com/aCEBAju/2/
In your original code you have this:
str.concat(inValue.charAt(index));
debugging in Chrome it barks: array has no method charAt.

The solution to the problem is that str.concat(inValue.charAt(index)); must change to str = str.concat(inValue.charAt(index)); or str += inValue.charAt(index);. Str must be assigned the new value. This is the entire working function:
var counter = 0;
function rotateTitle() {
var baseTitle = "www.berrmal.com - now with JavaScript";
var titleArray = new Array("b","e","r","r","m","a","l"); //no longer necessary
var titleString = "berrmal: bigger, longer, uncut";
var scrollText = getNextScroll(titleString);
window.document.title=baseTitle.concat(scrollText);
}
function getNextScroll(inString) {
var str = " ";
for (var i = 0; i<inString.length; i++) {
var index = i+counter;
if (i+counter >= inString.length) {
index -= inString.length;
}
str += inString.charAt(index);
}
counter++;
if (counter > inString.length) {
counter = 0;
}
return str;
}
I figured out the answer to the problem based on Leniel Macaferi's answer, though his posted code is not correct. This method runs successfully in Firefox 23.0 with no error in the console.

Using separators in JS

I'm currently writing a program that uses ";" as a seperator and extracts the url up until that point upon searching the content.
So it has the format:
name;surname
In searching the given arrays... I decided to go the extra mile and test for arrays without the ";" but this has confused the program - it has no idea of the ";" position anymore and this throws a spanner in the works!
Here is my code so far - many thanks in advance!
pages =
[
"The first", "An;alternative;page", "Yet another page"
]
u_c_pages =
[
"www.cam.ac.uk;"+pages[0]
,
"www.warwick.ac.uk"+pages[1]
,
"www.kcl.ac.uk;"+pages[1]
,
"www;"+pages[2]
]
var pattern5 = prompt('5) Please enter a search term:');
function url1_m1(u_c_pages,pattern)
{
var seperator = [];
var seperatorPos = [];
if(pattern)
{
for (var i = 0; i < u_c_pages.length; i++)
{
var found = true;
if((u_c_pages[i].indexOf(";"))<0)
{
found=false;
}
else
{
seperator[seperator.length] = i;
seperatorPos[seperatorPos.length] = (u_c_pages[i].indexOf("|"));
}
}
if(seperator.length==0)
{
return("Nothing found!");
}
else
var found2 = "";
{
for (var j = 0; j < seperator.length; j++)
{
if(u_c_pages[j].substring(seperatorPos[j],u_c_pages[j].length-1).toLowerCase().indexOf(pattern.toLowerCase()) >= 0)
{
found2 = (u_c_pages[j].substring(0,seperatorPos[j]));
break;
}
}
return(found2)
}
}
else
{
// only returned when the user decides to type in nothing
return("Nothing entered!");
}
}
alert(url1_m1(u_c_pages,pattern5));

enjoy the power of regex:
on JSFiddle
pages = ["The first", "An;alternative;page", "Yet another page"];
u_c_pages = [
"www.lboro.ac.uk;"+pages[0],
"www.xyz.ac.uk;"+pages[1],
"www.xyz.ac.uk;"+pages[1],
"www;"+pages[2]
];
var pattern5 = prompt('5) Please enter a search term:');
function url1_m1(u_c_pages,pattern)
{
// escape search pattern
pattern = pattern.toLowerCase().replace(/[-/\\^$*+?.()|[\]{}]/g, '\\$&')
pattern = new RegExp('^([^;]+);.*?' + pattern, 'i');
var result = null;
for(var i=0;i<u_c_pages.length;i++) {
if((result = u_c_pages[i].match(pattern))) {
return result[1];
}
}
return false;
}
alert(url1_m1(u_c_pages,pattern5));

You can use String.split(";") to split a string into segments. The parameter is the seperator.

Count BB code occurence

I want to count number of occurence of BB code like word (example: [b] [/b]).
I tried
(str.match(/\[b\]/g) str.match(/\[\/b\]/g))
None of this worked, please help !!!
Edit
document.getElementById('textarea').value = 'HIiiiiiiiiiii [b]BOld[/b]';
var str = document.getElementById('textarea').value;
Answer:
if (str.match(/\[b\]/g).length == str.match(/\[\/b\]/g)).length) {alert("Fine");}

This regex will match a BB code opening tag:
str.match(/\[[a-z]*\]/g)
Edit: Here's some code that will do exactly what you want including creating an array of errors listing all missing closing tags. This code uses the underscore library for the groupBy() call.
jsFiddle
var bbcode = 'HI[i]iii[i]iii[/i]iii [b]BOld[/b] yahhh [img]url[/img]';
var matches = bbcode.match(/\[[a-z]*\]/g); //get the matches
var tags = _.groupBy(matches, function(val) {
val = val.substring(1, val.length-1);
return val;
});
var errors = [];
for (var tag in tags) {
var regex = '\\\[/' + tag + '\\\]';
if (bbcode.match(regex).length != tags[tag].length) {
errors.push('Missing a closing [/' + tag + '] tag');
}
}
console.log(errors);

Replace occurences until there aren't any; keep track of the amount on the way:
var regexp = /\[[a-z]\](.*?)\[\/[a-z]\]/i;
var str = "test [b]a[/b] test [i]b[/i] [b]d[/b] c";
var newstr = str;
var i = 0;
while(regexp.test(newstr)) {
newstr = newstr.replace(regexp, "");
i++;
}
alert(i); // alerts 3

.read .write .replace string elements in jQuery

I have these 2 functions (serialize and deserialize) in Javascript (below) and I want to change it to jQuery. I am wondering what would the right replacement for read and write in jQuery. Read and write strings are from and to a Textarea. This is part of Openlayers vector formats, getting geometries into / from OL map canvas.
Serialize is outputing the geometries from mapcanvas to textarea.
function serialize(feature) {
var type = document.getElementById("formatType").value;
var pretty = document.getElementById("prettyPrint").checked;
var str = formats['out'][type].write(feature, pretty);
str = str.replace(/,/g, ', ');
document.getElementById('output').value = str;
}
Deserialize is reading string from Textarea into OL mapcanvas.
function deserialize() {
var element = document.getElementById('text');
var type = document.getElementById("formatType").value;
var features = formats['in'][type].read(element.value);
var bounds;
if(features) {
if(features.constructor != Array) {
features = [features];
}
for(var i=0; i<features.length; ++i) {
if (!bounds) {
bounds = features[i].geometry.getBounds();
} else {
bounds.extend(features[i].geometry.getBounds());
}
}
vectors.addFeatures(features);
map.zoomToExtent(bounds);
var plural = (features.length > 1) ? 's' : '';
element.value = features.length + ' feature' + plural + ' added';
} else {
element.value = 'Bad input ' + type;
}
}
Thanks in advance.
Again, I am asking about the read and write function equivalent in jQuery. These 2 lines:
var str = formats['out'][type].write(feature, pretty);
var features = formats['in'][type].read(element.value);

to get the text in a text area
$("#myTextArea").val();
To set it to something
$("#myTextArea").val("Foo bar.");

Making a variable name a dynamic variable

I hope someone can help me with the following...
I have this code below it is written in classic asp and javascript...
I have this variable in the code below my2String1 how can I make this a dynamic variable like:
my2String1_1
my2String1_2
my2String1_3
I have a database value Recordset2.Fields.Item("article_no").Value which could be the dynamic value like:
my2String1_Recordset2.Fields.Item("article_no").Value (which should do the trick) but I am not sure how to implement it...
while((Repeat1__numRows-- != 0) && (!Recordset2.EOF)) {
var my2String1 = ""+(Recordset2.Fields.Item("article_description").Value)+"";
my2String = my2String1;
var my2regexp = new RegExp(checkduplicates, "ig");
my2Array = my2String1.match(my2regexp);
my2length = my2Array.length;
for (i = 0; i < my2length; i++) {
my2Array[i] = '\''+my2Array[i]+'\'';
}
var arr = (myArray+my2Array).split(',');
var sorted_arr = arr.sort();
var results = [];
for (var i = 0; i < arr.length - 1; i += 1) {
if (sorted_arr[i + 1] == sorted_arr[i]) {
results.push(sorted_arr[i]);
}
}
Repeat1__index++;
Recordset2.MoveNext();
}
If you have any ideas on how to solve this please help me

I'm going to ignore that load of code because it clouding the issue. The feature of JScript you are looking to for is the ability to create named properties on an object:-
var myDescriptions = {}
var name = "Test"
var description = "This is a test"
myDescriptions[name] = description;
Response.Write(myDescriptions[name]);
Would send "This is a test" to the response.