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Javascript taking too long to run

I have a script that is taking too long to run and that is causing me This error on ie : a script on this page is causing internet explorer to run slowly.
I have read other threads concerning this error and have learned that there is a way to by pass it by putting a time out after a certain number of iterations.
Can u help me apply a time out on the following function please ?
Basically each time i find a hidden imput of type submit or radio i want to remove and i have a lot of them . Please do not question why do i have a lots of hidden imputs. I did it bc i needed it just help me put a time out please so i wont have the JS error. Thank you
$('input:hidden').each(function(){
var name = $(this).attr('name');
if($("[name='"+name+"']").length >1){
if($(this).attr('type')!=='radio' && $(this).attr('type')!=='submit'){
$(this).remove();
}
}
});
One of the exemples i found : Bypassing IE's long-running script warning using setTimeout

You may want to add input to your jquery selector to filter out only input tags.
if($("input[name='"+name+"']").length >1){

Here's the same code optimised a bit without (yet) using setTimeout():
var $hidden = $('input:hidden'),
el;
for (var i = 0; i < $hidden.length; i++) {
el = $hidden[i];
if(el.type!=='radio' && el.type!=='submit'
&& $("[name='" + el.name + "']").length >1) {
$(el).remove();
}
}
Notice that now there is a maximum of three function calls per iteration, whereas the original code had up to ten function calls per iteration. There's no need for, say, $(this).attr('type') (two function calls) when you can just say this.type (no function calls).
Also, the .remove() only happens if three conditions are true, the two type tests and check for other elements of the same name. Do the type tests first, because they're quick, and only bother doing the slow check for other elements if the type part passes. (JS's && doesn't evaluate the right-hand operand if the left-hand one is falsy.)
Or with setTimeout():
var $hidden = $('input:hidden'),
i = 0,
el;
function doNext() {
if (i < $hidden.length) {
el = $hidden[i];
if(el.type!=='radio' && el.type!=='submit'
&& $("[name='" + el.name + "']").length >1) {
$(el).remove();
}
i++;
setTimeout(doNext, 0);
}
}
doNext();
You could improve either version by changing $("[name='" + el.name + "']") to specify a specific element type, e.g., if you are only doing inputs use $("input[name='" + el.name + "']"). Also you could limit by some container, e.g., if those inputs are all in a form or something.

It looks like the example you cited is exactly what you need. I think if you take your code and replace the while loop in the example (keep the if statement for checking the batch size), you're basically done. You just need the jQuery version of breaking out of a loop.

To risk stating the obvious; traversing through the DOM looking for matches to these CSS selectors is what's making your code slow. You can cut down the amount of work it's doing with a few simple tricks:
Are these fields inside a specific element? If so you can narrow the search by including that element in the selector.
e.g:
$('#container input:hidden').each(function(){
...
You can also narrow the number of fields that are checked for the name attribute
e.g:
if($("#container input[name='"+name+"']").length >1){
I'm also unclear why you're searching again with $("[name='"+name+"']").length >1once you've found the hidden element. You didn't explain that requirement. If you don't need that then you'll speed this up hugely by taking it out.
$('#container input:hidden').each(function(){
var name = $(this).attr('name');
if($(this).attr('type')!=='radio' && $(this).attr('type')!=='submit'){
$(this).remove();
}
});
If you do need it, and I'd be curious to know why, but the best approach might be to restructure the code so that it only checks the number of inputs for a given name once, and removes them all in one go.

Try this:
$("[type=hidden]").remove(); // at the place of each loop
It will take a short time to delete all hidden fields.
I hope it will help.
JSFiddle example

Select tags that starts with "x-" in jQuery

How can I select nodes that begin with a "x-" tag name, here is an hierarchy DOM tree example:
<div>
<x-tab>
<div></div>
<div>
<x-map></x-map>
</div>
</x-tab>
</div>
<x-footer></x-footer>
jQuery does not allow me to query $('x-*'), is there any way that I could achieve this?

The below is just working fine. Though I am not sure about performance as I am using regex.
$('body *').filter(function(){
return /^x-/i.test(this.nodeName);
}).each(function(){
console.log(this.nodeName);
});
Working fiddle
PS: In above sample, I am considering body tag as parent element.
UPDATE :
After checking Mohamed Meligy's post, It seems regex is faster than string manipulation in this condition. and It could become more faster (or same) if we use find. Something like this:
$('body').find('*').filter(function(){
return /^x-/i.test(this.nodeName);
}).each(function(){
console.log(this.nodeName);
});
jsperf test
UPDATE 2:
If you want to search in document then you can do the below which is fastest:
$(Array.prototype.slice.call(document.all)).filter(function () {
return /^x-/i.test(this.nodeName);
}).each(function(){
console.log(this.nodeName);
});
jsperf test

There is no native way to do this, it has worst performance, so, just do it yourself.
Example:
var results = $("div").find("*").filter(function(){
return /^x\-/i.test(this.nodeName);
});
Full example:
http://jsfiddle.net/6b8YY/3/
Notes: (Updated, see comments)
If you are wondering why I use this way for checking tag name, see:
JavaScript: case-insensitive search
and see comments as well.
Also, if you are wondering about the find method instead of adding to selector, since selectors are matched from right not from left, it may be better to separate the selector. I could also do this:
$("*", $("div")). Preferably though instead of just div add an ID or something to it so that parent match is quick.
In the comments you'll find a proof that it's not faster. This applies to very simple documents though I believe, where the cost of creating a jQuery object is higher than the cost of searching all DOM elements. In realistic page sizes though this will not be the case.
Update:
I also really like Teifi's answer. You can do it in one place and then reuse it everywhere. For example, let me mix my way with his:
// In some shared libraries location:
$.extend($.expr[':'], {
x : function(e) {
return /^x\-/i.test(this.nodeName);
}
});
// Then you can use it like:
$(function(){
// One way
var results = $("div").find(":x");
// But even nicer, you can mix with other selectors
// Say you want to get <a> tags directly inside x-* tags inside <section>
var anchors = $("section :x > a");
// Another example to show the power, say using a class name with it:
var highlightedResults = $(":x.highlight");
// Note I made the CSS class right most to be matched first for speed
});
It's the same performance hit, but more convenient API.

It might not be efficient, but consider it as a last option if you do not get any answer.
Try adding a custom attribute to these tags. What i mean is when you add a tag for eg. <x-tag>, add a custom attribute with it and assign it the same value as the tag, so the html looks like <x-tag CustAttr="x-tag">.
Now to get tags starting with x-, you can use the following jQuery code:
$("[CustAttr^=x-]")
and you will get all the tags that start with x-

custom jquery selector
jQuery(function($) {
$.extend($.expr[':'], {
X : function(e) {
return /^x-/i.test(e.tagName);
}
});
});
than, use $(":X") or $("*:X") to select your nodes.

Although this does not answer the question directly it could provide a solution, by "defining" the tags in the selector you can get all of that type?
$('x-tab, x-map, x-footer')

Workaround: if you want this thing more than once, it might be a lot more efficient to add a class based on the tag - which you only do once at the beginning, and then you filter for the tag the trivial way.
What I mean is,
function addTagMarks() {
// call when the document is ready, or when you have new tags
var prefix = "tag--"; // choose a prefix that avoids collision
var newbies = $("*").not("[class^='"+prefix+"']"); // skip what's done already
newbies.each(function() {
var tagName = $(this).prop("tagName").toLowerCase();
$(this).addClass(prefix + tagName);
});
}
After this, you can do a $("[class^='tag--x-']") or the same thing with querySelectorAll and it will be reasonably fast.

See if this works!
function getXNodes() {
var regex = /x-/, i = 0, totalnodes = [];
while (i !== document.all.length) {
if (regex.test(document.all[i].nodeName)) {
totalnodes.push(document.all[i]);
}
i++;
}
return totalnodes;
}

Demo Fiddle
var i=0;
for(i=0; i< document.all.length; i++){
if(document.all[i].nodeName.toLowerCase().indexOf('x-') !== -1){
$(document.all[i].nodeName.toLowerCase()).addClass('test');
}
}

Try this
var test = $('[x-]');
if(test)
alert('eureka!');
Basically jQuery selector works like CSS selector.
Read jQuery selector API here.

Regex for visible text, not HTML

If i had a string:
hey user, what are you doing?
How, with regex could I say: look for user, but not inside of < or > characters? So the match would grab the user between the <a></a> but not the one inside of the href
I'd like this to work for any tag, so it wont matter what tags.
== Update ==
Why i can't use .text() or innerText is because this is being used to highlight results much like the native cmd/ctrl+f functionality in browsers and I dont want to lose formatting. For example, if i search for strong here:
Some <strong>strong</strong> text.
If i use .text() itll return "Some strong text" and then I'll wrap strong with a <span> which has a class for styling, but now when I go back and try to insert this into the DOM it'll be missing the <strong> tags.

If you plan to replace the HTML using html() again then you will loose all event handlers that might be bound to inner elements and their data (as I said in my comment).
Whenever you set the content of an element as HTML string, you are creating new elements.
It might be better to recursively apply this function to every text node only. Something like:
$.fn.highlight = function(word) {
var pattern = new RegExp(word, 'g'),
repl = '<span class="high">' + word + '</span>';
this.each(function() {
$(this).contents().each(function() {
if(this.nodeType === 3 && pattern.test(this.nodeValue)) {
$(this).replaceWith(this.nodeValue.replace(pattern, repl));
}
else if(!$(this).hasClass('high')) {
$(this).highlight(word);
}
});
});
return this;
};
DEMO
It could very well be that this is not very efficient though.

To emulate Ctrl-F (which I assume is what you're doing), you can use window.find for Firefox, Chrome, and Safari and TextRange.findText for IE.
You should use a feature detect to choose which method you use:
function highlightText(str) {
if (window.find)
window.find(str);
else if (window.TextRange && window.TextRange.prototype.findText) {
var bodyRange = document.body.createTextRange();
bodyRange.findText(str);
bodyRange.select();
}
}
Then, after you the text is selected, you can style the selection with CSS using the ::selection selector.
Edit: To search within a certain DOM object, you could use a roundabout method: use window.find and see whether the selection is in a certain element. (Perhaps say s = window.getSelection().anchorNode and compare s.parentNode == obj, s.parentNode.parentNode == obj, etc.). If it's not in the correct element, repeat the process. IE is a lot easier: instead of document.body.createTextRange(), you can use obj.createTextRange().

$("body > *").each(function (index, element) {
var parts = $(element).text().split("needle");
if (parts.length > 1)
$(element).html(parts.join('<span class="highlight">needle</span>'));
});
jsbin demo
at this point it's evolving to be more and more like Felix's, so I think he's got the winner
original:
If you're doing this in javascript, you already have a handy parsed version of the web page in the DOM.
// gives "user"
alert(document.getElementById('user').innerHTML);
or with jQuery you can do lots of nice shortcuts:
alert($('#user').html()); // same as above
$("a").each(function (index, element) {
alert(element.innerHTML); // shows label text of every link in page
});

I like regexes, but because tags can be nested, you will have to use a parser. I recommend http://simplehtmldom.sourceforge.net/ it is really powerful and easy to use. If you have wellformed xhtml you can also use SimpleXML from php.
edit: Didn't see the javascript tag.

Try this:
/[(<.+>)(^<)]*user[(^>)(<.*>)]/
It means:
Before the keyword, you can have as many <...> or non-<.
Samewise after it.
EDIT:
The correct one would be:
/((<.+>)|(^<))*user((^>)|(<.*>))*/

Here is what works, I tried it on your JS Bin:
var s = 'hey user, what are you doing?';
s = s.replace(/(<[^>]*)user([^<]>)/g,'$1NEVER_WRITE_THAT_ANYWHERE_ELSE$2');
s = s.replace(/user/g,'Mr Smith');
s = s.replace(/NEVER_WRITE_THAT_ANYWHERE_ELSE/g,'user');
document.body.innerHTML = s;
It may be a tiny little bit complicated, but it works!
Explanation:
You replace "user" that is in the tag (which is easy to find) with a random string of your choice that you must never use again... ever. A good use would be to replace it with its hashcode (md5, sha-1, ...)
Replace every remaining occurence of "user" with the text you want.
Replace back your unique string with "user".

this code will strip all tags from sting
var s = 'hey user, what are you doing?';
s = s.replace(/<[^<>]+>/g,'');

Javascript Regex and getElementByID

I'm trying to search for all elements in a web page with a certain regex pattern.
I'm failing to understand how to utilize Javascript's regex object for this task. My plan was to collect all elements with a jQuery selector
$('div[id*="Prefix_"]');
Then further match the element ID in the collection with this
var pattern = /Prefix_/ + [0 - 9]+ + /_Suffix$/;
//Then somehow match it.
//If successful, modify the element in some way, then move onto next element.
An example ID would be "Prefix_25412_Suffix". Only the 5 digit number changes.
This looks terrible and probably doesn't work:
1) I'm not sure if I can store all of what jQuery's returned into a collection and then iterate through it. Is this possible?? If I could I could proceed with step two. But then...
2) What function would I be using for step 2? The regex examples all use String.match method. I don't believe something like element.id.match(); is valid?
Is there an elegant way to run through the elements identified with a specific regex and work with them?
Something in the vein of C#
foreach (element e in
ElementsCollectedFromIDRegexMatch) { //do stuff }

Just use the "filter" function:
$('div[id*=Prefix_]').filter(function() {
return /^Prefix_\d+_Suffix$/.test(this.id);
}).each(function() {
// whatever you need to do here
// "this" will refer to each element to be processed
});
Using what jQuery returns as a collection and iterating through it is, in fact, the fundamental point of the whole library, so yes you can do that.
edit — a comment makes me realize that the initial selector with the "id" test is probably not useful; you could just operate on all the <div> elements on the page to start with, and let your own filtering pluck out the ones you really want.

You can use filter function. i.e:
$('div[id*="Prefix_"]').filter(function(){
return this.id.match(/Prefix_\d+_Suffix/);
});

You could do something like
$('div[id*="Prefix_"]').each(function(){
if($(this).attr('id').search(/do your regex here/) != -1) {
//change the dom element here
}
});

You could try using the filter method, to do something like this...
var pattern = /Prefix_/ + [0 - 9]+ + /_Suffix$/;
$('div[id*="Prefix_"]').filter(function(index)
{
return $(this).attr("id").search(pattern) != -1;
}
);
... and return a jQuery collection that contains all (if any) of the elements which match your spec.
Can't be sure of the exact syntax, off the top of my head, but this should at least point you in the right direction

jQuery replace strings in many classes

I'm trying to use jQuery to replace all occurrences of a particular string that occurs in a certain class. There are multiple classes of this type on the page.
So far I have the following code:
var el = $('div.myclass');
if(el != null && el.html() != null )
{
el.html(el.html().replace(/this/ig, "that"));
}
This doesn't work if there is more than one div with class myclass. If there is more than one div then the second div is replaced with the contents of the first! It is as if jQuery performs the replacement on the first div and then replaces all classes of myclass with the result.
Anyone know how I should be doing this? I'm thinking some kind of loop over all instances of mychass divs - but my JS is a bit weak.

I think what you are looking for is something like this:
$('div.myclass').each(function(){
var content = $(this).html();
content = content.replace(/this/ig,'that');
$(this).html(content);
});
(not tested)

slightly different of previous answer:
$('div.myclass').each(function(i, el) {
if($(el).html() != "" ) {
$(el).html($(el).html().replace(/this/ig, "that"));
}
});
should work

If the contents of your .myclass elements are purely textual, you can get away with this. But if they contain other elements your regex processing might change attribute values by mistake. Don't process HTML with regex.
Also by writing to the innerHTML/html(), you would lose any non-serialisable data in any child element, such as form field values, event handlers and other JS references.
function isTextNode(){
return this.nodeType===3; // Node.TEXT_NODE
}
$('div.myclass, div.myclass *').each(function () {
$(this).contents().filter(isTextNode).each(function() {
this.data= this.data.replace(/this/g, 'that');
});
});