load jquery after the page is fully loaded

load jquery after the page is fully loaded - javascript

I'm looking for a way to load jquery after the page is fully loaded.
well there are lots of questions and answers about it in here, but all describe how to run a script that needs jquery after either page or jquery fully loaded.
What I'm looking for is to load the page and then call jquery and after the jquery is loaded call the functions. something like:
document.onload=function(){
var fileref=document.createElement('script');
fileref.setAttribute("type","text/javascript");
fileref.setAttribute("src", 'http://code.jquery.com/jquery-1.7.2.min.js');
//Here I need an event to know that jquery is
//loaded to run stuff that needs jquery
}

Try this:
$(document).ready(function() {
// When the document is ready
// Do something
});

You can also use:
$(window).bind("load", function() {
// Your code here.
});

For your problem, the solution might be to attach CDN hosted by google with certain library:
https://developers.google.com/speed/libraries/devguide
Also, you can add this at the bottom of page (just before </body>):
<script type="text/javascript">
(function() {
var script = document.createElement('script')
script.setAttribute("type", "text/javascript")
script.setAttribute("src", "https://ajax.googleapis.com/ajax/libs/jquery/2.0.3/jquery.min.js")
document.getElementsByTagName("head")[0].appendChild(script)
})();
</script>
However, this is risky in my opinion. You have an asynchronous call for jquery, thus your jquery has to wait until it loads (ie. $(document).ready won't work in this case). So my answer would be: use a CDN like google suggests; put your javascript on the bottom just before </body>; and, ignore flags from profilers.

It is advised to load your scripts at the bottom of your <body> block to speed up the page load, like this:
<body>
<!-- your content -->
<!-- your scripts -->
<script src=".."></script>
</body>
</html>

You can either use .onload function. It runs a function when the page is fully loaded including graphics.
window.onload=function(){
// Run code
};
Or another way is : Include scripts at the bottom of your page.

You can try using your function and using a timeout waiting until the jQuery object is loaded
Code:
document.onload=function(){
var fileref=document.createElement('script');
fileref.setAttribute("type","text/javascript");
fileref.setAttribute("src", 'http://code.jquery.com/jquery-1.7.2.min.js');
document.getElementsByTagName("head")[0].appendChild(fileref);
waitForjQuery();
}
function waitForjQuery() {
if (typeof jQuery != 'undefined') {
// do some stuff
} else {
window.setTimeout(function () { waitForjQuery(); }, 100);
}
}

My guess is that you load jQuery in the <head> section of your page. While this is not harmful, it slows down page load. Try using this pattern to speed up initial loading time of the DOM-Tree:
<!doctype html>
<html>
<head>
<title></title>
<meta charset="utf-8">
<!-- CSS -->
<link rel="stylesheet" type="text/css" href="">
</head>
<body>
<!-- PAGE CONTENT -->
<!-- JS -->
<script type="text/javascript" src="http://code.jquery.com/jquery-1.7.2.min.js"></script>
<script>
$(function() {
$('body').append('<p>I can happily use jQuery</p>');
});
</script>
</body>
</html>
Just add your scripts at the end of your <body>tag.
There are some scripts that need to be in the head due to practical reasons, the most prominent library being Modernizr

if you can load jQuery from your own server, then you can append this to your jQuery file:
jQuery(document).trigger('jquery.loaded');
then you can bind to that triggered event.

Include your scripts at the bottom of the page before closing body tag.
More info HERE.

If you're trying to avoid loading jquery until your content has been loaded, the best way is to simply put the reference to it in the bottom of your page, like many other answers have said.
General tips on Jquery usage:
Use a CDN. This way, your site can use the cached version a user likely has on their computer. The // at the beginning allows it to be called (and use the same resource) whether it's http or https. Example:
<script src="//ajax.googleapis.com/ajax/libs/jquery/1.11.1/jquery.min.js"></script>
Using a CDN has a couple of big benefits: it makes it more likely that users have it cached from another site, so there will be no download (and no render-blocking). Further, CDNs use the closest, fastest connection available, meaning that if they do need to load it, it will probably be faster than connecting to your server. More info from Google.
Put scripts at the bottom. Move as much of your js to the bottom of the page as possible. I use php to include a file with all my JS resources below the footer.
If you're using a template system, you may need to have javascript spread throughout the html output. If you're using jquery in scripts that get called as the page renders, this will cause errors. To have your scripts wait until jquery is loaded, put them into
window.onload() = function () { //... your js that isn't called by user interaction ... }
This will prevent errors but still run before user interaction and without timers.
Of course, if jquery is cached, it won't matter too much where you put it, except to page speed tools that will tell you you're blocking rendering.

I have asked this question more than 6 years ago, and any answers I got had some flaws. Later I myself worked out a solution that I have been using for years since then. Now that I came across my own question again and I saw that it has many views, I'd like to share it because I think it may help others.
This problem mainly occurs on Master-Detail type of pages (can be old .master and .aspx pages) or (layout and views in asp.net) or any similar situation maybe on other web development languages, however always there is a master-detail pattern involved.
For the solution, I just add an array at the beginning of my page:
<script>var after = [];</script>
any function that requires jQuery or any other script that would run after this section, instead of running it, I just push it to this array:
after.push(function(){
// code that requires scripts that will load later,
//might be for example a jQuery selector or ...
});
and then at the very end of the page, right before closing the body tag (of course scripts are loaded by now) I run all the functions inside the (here named) after array:
<script>for(var i=0;i<after.length;i++)after[i]();</script>
</body>
I find this way very easy, simple and flawless.

Related

Can I use JS to add async to a script tag in an iframe in such a way that it will actually affect the script page loading?

It seems that the Stripe JavaScript is adding nearly 1/2 a second of main-thread blocking to my site. According to the Stripe documentation, it's totally fine to either async or defer their JS. In fact, they say that if you include it through npm it does this automatically. This is probably what I would have done if I were implementing this on my own, but I'm using Stripe through a WordPress plugin that, whatever they're doing, is pulling the Stripe JS in through an iFrame, and not setting async:
<iframe name="__privateStripeController5481" ...>
<!DOCTYPE html>
<html lang="en">
<head>
<script src="https://js.stripe.com/v3/fingerprinted/js/shared-0950781806f615c0693abdcbbb4bfc19.js"></script>
<script src="https://js.stripe.com/v3/fingerprinted/js/controller-842819e3871bc12ac5b51fa16b375c03.js"></script>
</head>
<body></body>
</html>
</iframe>
I'm thinking there should be some way to fix this, without waiting on the plugin developers to do it on their own. My idea is to do something like:
document.getElementById('ifrm').onload = function() {
const ifrm = document.getElementById('ifrm');
const scripts = ifrm.contentDocument?
ifrm.contentDocument: ifrm.contentWindow.document.getElementsByTagName('script');
for (const element of scripts) {
element.hasAttribute('async') ? {} : element.setAttribute('async', '');
}
};
But onload, will, I'm pretty sure, be way too late. Is there a way to accomplish this modification such that it happens early enough that the scripts in the iFrame end up being non-blocking?

No, you can't change how the script tag is processed after the browser has read it from the HTML and started processing it. (Not least because your page and the iframe are running on the same one main UI thread — the very thread being blocked by that script tag.)
You'll have to modify the plugin's code. (And perhaps do a PR to get it adopted by the plugin project maintainers.)

$ is not defined jQuery 3.5.1 window on load [duplicate]

I have a simple jquery click event
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>
and a jquery reference defined in the site.master
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
I have checked that the script is being resolved correctly, I'm able to see the markup and view the script directly in firebug, so I must be being found. However, I am still getting:
$ is not defined
and none of the jquery works. I've also tried the various variations of this like $(document).ready and jQuery etc.
It's an MVC 2 app on .net 3.5, I'm sure I'm being really dense, everywhere on google says to check the file is referenced correctly, which I have checked and checked again, please advise! :/

That error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may have overwritten the $ variable.
You have JavaScript running before the page is fully loaded, and as such, before jQuery is fully loaded.
First of all, ensure, what script is call properly, it should looks like
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
and shouldn't have attributes async or defer.
Then you should check the Firebug net panel to see if the file is actually being loaded properly. If not, it will be highlighted red and will say "404" beside it. If the file is loading properly, that means that the issue is number 2.
Make sure all jQuery javascript code is being run inside a code block such as:
$(document).ready(function () {
//your code here
});
This will ensure that your code is being loaded after jQuery has been initialized.
One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described.
Note: If you're loading code which does not require jQuery to run it does not need to be placed inside the jQuery ready handler. That code may be separated using document.readyState.

It could be that you have your script tag called before the jquery script is called.
<script type="text/javascript" src="js/script.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
This results as $ is not defined
Put the jquery.js before your script tag and it will work ;) like so:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript" src="js/script.js"></script>

First you need to make sure that jQuery script is loaded. This could be from a CDN or local on your website. If you don't load this first before trying to use jQuery it will tell you that jQuery is not defined.
<script src="jquery.min.js"></script>
This could be in the HEAD or in the footer of the page, just make sure you load it before you try to call any other jQuery stuff.
Then you need to use one of the two solutions below
(function($){
// your standard jquery code goes here with $ prefix
// best used inside a page with inline code,
// or outside the document ready, enter code here
})(jQuery);
or
jQuery(document).ready(function($){
// standard on load code goes here with $ prefix
// note: the $ is setup inside the anonymous function of the ready command
});
please be aware that many times $(document).ready(function(){//code here}); will not work.

If the jQuery plugin call is next to the </body>, and your script is loaded before that, you should make your code run after window.onload event, like this:
window.onload = function() {
//YOUR JQUERY CODE
}
`
so, your code will run only after the window load, when all assets have been loaded. In that point, the jQuery ($) will be defined.
If you use that:
$(document).ready(function () {
//YOUR JQUERY CODE
});
`
the $ isn't yet defined at this time, because it is called before the jQuery is loaded, and your script will fail on that first line on console.

I just did the same thing and found i had a whole lot of
type="text/javacsript"
So they were loading, but no further hint as to why it wasn't working. Needless to say, proper spelling fixed it.

Use a scripts section in the view and master layout.
Put all your scripts defined in your view inside a Scripts section of the view. This way you can have the master layout load this after all other scripts have been loaded. This is the default setup when starting a new MVC5 web project. Not sure about earlier versions.
Views/Foo/MyView.cshtml:
// The rest of your view code above here.
#section Scripts
{
// Either render the bundle defined with same name in BundleConfig.cs...
#Scripts.Render("~/bundles/myCustomBundle")
// ...or hard code the HTML.
<script src="URL-TO-CUSTOM-JS-FILE"></script>
<script type="text/javascript">
$(document).ready(function () {
// Do your custom javascript for this view here. Will be run after
// loading all the other scripts.
});
</script>
}
Views/Shared/_Layout.cshtml
<html>
<body>
<!-- ... Rest of your layout file here ... -->
#Scripts.Render("~/bundles/jquery")
#Scripts.Render("~/bundles/bootstrap")
#RenderSection("scripts", required: false)
</body>
</html>
Note how the scripts section is rendered last in the master layout file.

It means that your jQuery library has not been loaded yet.
You can move your code after pulling jQuery library.
or you can use something like this
window.onload = function(){
// Your code here
// $(".some-class").html("some html");
};

As stated above, it happens due to the conflict of $ variable.
I resolved this issue by reserving a secondary variable for jQuery with no conflict.
var $j = jQuery.noConflict();
and then use it anywhere
$j( "div" ).hide();
more details can be found here

make sure you really load jquery
this is not jquery - it's the ui!
<script language="JavaScript"
src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.10.0/jquery-ui.min.js">
</script>
This is a correct script source for jquery:
<script language="JavaScript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>

Are you using any other JavaScript libraries? If so, you will probably need to use jQuery in compatibility mode:
http://docs.jquery.com/Using_jQuery_with_Other_Libraries

after some tests i found a fast solution ,
you can add in top of your index page:
<script>
$=jQuery;
</script>
it work very fine :)

I had the same problem and resolved it by using
document.addEventListener('DOMContentLoaded', () => {
// code here
});

I got the same error message when I misspelled the jQuery reference and instead of type="text/javascript" I typed "...javascirpt". ;)

It sounds like jQuery isn't loading properly. Which source/version are you using?
Alternatively, it could a be namespace collision, so try using jQuery explicitly instead of using $. If that works, you may like to use noConflict to ensure the other code that's using $ doesn't break.

That error means that jQuery has not yet loaded on the page. Using $(document).ready(...) or any variant thereof will do no good, as $ is the jQuery function.
Using window.onload should work here. Note that only one function can be assigned to window.onload. To avoid losing the original onload logic, you can decorate the original function like so:
originalOnload = window.onload;
window.onload = function() {
if (originalOnload) {
originalOnload();
}
// YOUR JQUERY
};
This will execute the function that was originally assigned to window.onload, and then will execute // YOUR JQUERY.
See https://en.wikipedia.org/wiki/Decorator_pattern for more detail about the decorator pattern.

I use Url.Content and never have a problem.
<script src="<%= Url.Content ("~/Scripts/jquery-1.4.1.min.js") %>" type="text/javascript"></script>

In the solution it is mentioned -
"One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described."
For avoiding this -
Many JavaScript libraries use $ as a function or variable name, just as jQuery does. In jQuery's case, $ is just an alias for jQuery, so all functionality is available without using $. If we need to use another JavaScript library alongside jQuery, we can return control of $ back to the other library with a call to $.noConflict():

I had this problem once for no apparent reason. It was happenning locally whilst I was running through the aspnet development server. It had been working and I reverted everything to a state where it had previously been working and still it didn't work. I looked in the chrome debugger and the jquery-1.7.1.min.js had loaded without any problems. It was all very confusing. I still don't know what the problem was but closing the browser, closing the development server and then trying again sorted it out.

Just place jquery url on the top of your jquery code
like this--
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>

I had the same problem and it was because my reference to the jQuery.js was not in the tag. Once I switched that, everything started working.
Anthony

Check the exact path of your jquery file is included.
<script src="assets/plugins/jquery/jquery.min.js"></script>
if you add this on bottom of your page , please all call JS function below this declaration.
Check using this code test ,
<script type="text/javascript">
/***
* Created by dadenew
* Submit email subscription using ajax
* Send email address
* Send controller
* Recive response
*/
$(document).ready(function() { //you can replace $ with Jquery
alert( 'jquery working~!' );
});
Peace!

This is the common issue to resolve this you have to check some point
Include Main Jquery Library
Check Cross-Browser Issue
Add Library on TOP of the jquery code
Check CDNs might be blocked.
Full details are given in this blog click here

I came across same issue, and it resolved by below steps.
The sequence of the scripts should be as per mentioned below
<script src="~/Scripts/jquery-3.3.1.min.js"></script>
<script src="~/Scripts/jquery-ui.js"></script>
<script src="~/Scripts/bootstrap.min.js"></script>
This sequence was not correct for my code, I corrected this as per the above and it resolved my issue of Jquery not defined.

We have the same problem....but accidentally i checked folder properties and set something...
You have to check the properties of each folders that you're accessing..
right click folder
'permissions' tab
set the folder access :
OWNER: create and delete files
GROUP: access files
OTHERS: access files
I hope that this is the solution......

When using jQuery in asp.net, if you are using a master page and you are loading the jquery source file there, make sure you have the header contentplaceholder after all the jquery script references.
I had a problem where any pages that used that master page would return '$ is not defined' simply because the incorrect order was making the client side code run before the jquery object was created. So make sure you have:
<head runat="server">
<script type="text/javascript" src="Scripts/jquery-VERSION#.js"></script>
<asp:ContentPlaceHolder id="Header" runat="server"></asp:ContentPlaceHolder>
</head>
That way the code will run in order and you will be able to run jQuery code on the child pages.

In my case I was pointing to Google hosted JQuery. It was included properly, but I was on an HTTPS page and calling it via HTTP. Once I fixed the problem (or allowed insecure content), it fired right up.

After tried everything here with no result, I solved the problem simply by moving the script src tag from body to head

I was having this same problem and couldn't figure out what was causing it. I recently converted my HTML files from Japanese to UTF-8, but I didn't do anything with the script files. Somehow jquery-1.10.2.min.js became corrupted in this process (I still have no idea how). Replacing jquery-1.10.2.min.js with the original fixed it.

it appears that if you locate your jquery.js files under the same folder or in some subfolders where your html file is, the Firebug problem is solved. eg if your html is under C:/folder1/, then your js files should be somewhere under C:/folder1/ (or C:/folder1/folder2 etc) as well and addressed accordingly in the html doc. hope this helps.

I have the same issue and no case resolve me the problem. The only thing that works for me, it's put on the of the Site.master file, the next:
<script src="<%= ResolveUrl("~/Scripts/jquery-1.7.1.min.js") %>" type="text/javascript"></script>
<script src="<%= ResolveUrl("~/Scripts/bootstrap/js/bootstrap.min.js") %>" type="text/javascript"></script>
With src="<%= ResolveUrl("")... the load of jQuery in the Content Pages is correct.

Javascript not working in my htm bootstrap [duplicate]

I have a simple jquery click event
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>
and a jquery reference defined in the site.master
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
I have checked that the script is being resolved correctly, I'm able to see the markup and view the script directly in firebug, so I must be being found. However, I am still getting:
$ is not defined
and none of the jquery works. I've also tried the various variations of this like $(document).ready and jQuery etc.
It's an MVC 2 app on .net 3.5, I'm sure I'm being really dense, everywhere on google says to check the file is referenced correctly, which I have checked and checked again, please advise! :/

That error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may have overwritten the $ variable.
You have JavaScript running before the page is fully loaded, and as such, before jQuery is fully loaded.
First of all, ensure, what script is call properly, it should looks like
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
and shouldn't have attributes async or defer.
Then you should check the Firebug net panel to see if the file is actually being loaded properly. If not, it will be highlighted red and will say "404" beside it. If the file is loading properly, that means that the issue is number 2.
Make sure all jQuery javascript code is being run inside a code block such as:
$(document).ready(function () {
//your code here
});
This will ensure that your code is being loaded after jQuery has been initialized.
One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described.
Note: If you're loading code which does not require jQuery to run it does not need to be placed inside the jQuery ready handler. That code may be separated using document.readyState.

It could be that you have your script tag called before the jquery script is called.
<script type="text/javascript" src="js/script.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
This results as $ is not defined
Put the jquery.js before your script tag and it will work ;) like so:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript" src="js/script.js"></script>

First you need to make sure that jQuery script is loaded. This could be from a CDN or local on your website. If you don't load this first before trying to use jQuery it will tell you that jQuery is not defined.
<script src="jquery.min.js"></script>
This could be in the HEAD or in the footer of the page, just make sure you load it before you try to call any other jQuery stuff.
Then you need to use one of the two solutions below
(function($){
// your standard jquery code goes here with $ prefix
// best used inside a page with inline code,
// or outside the document ready, enter code here
})(jQuery);
or
jQuery(document).ready(function($){
// standard on load code goes here with $ prefix
// note: the $ is setup inside the anonymous function of the ready command
});
please be aware that many times $(document).ready(function(){//code here}); will not work.

If the jQuery plugin call is next to the </body>, and your script is loaded before that, you should make your code run after window.onload event, like this:
window.onload = function() {
//YOUR JQUERY CODE
}
`
so, your code will run only after the window load, when all assets have been loaded. In that point, the jQuery ($) will be defined.
If you use that:
$(document).ready(function () {
//YOUR JQUERY CODE
});
`
the $ isn't yet defined at this time, because it is called before the jQuery is loaded, and your script will fail on that first line on console.

I just did the same thing and found i had a whole lot of
type="text/javacsript"
So they were loading, but no further hint as to why it wasn't working. Needless to say, proper spelling fixed it.

Use a scripts section in the view and master layout.
Put all your scripts defined in your view inside a Scripts section of the view. This way you can have the master layout load this after all other scripts have been loaded. This is the default setup when starting a new MVC5 web project. Not sure about earlier versions.
Views/Foo/MyView.cshtml:
// The rest of your view code above here.
#section Scripts
{
// Either render the bundle defined with same name in BundleConfig.cs...
#Scripts.Render("~/bundles/myCustomBundle")
// ...or hard code the HTML.
<script src="URL-TO-CUSTOM-JS-FILE"></script>
<script type="text/javascript">
$(document).ready(function () {
// Do your custom javascript for this view here. Will be run after
// loading all the other scripts.
});
</script>
}
Views/Shared/_Layout.cshtml
<html>
<body>
<!-- ... Rest of your layout file here ... -->
#Scripts.Render("~/bundles/jquery")
#Scripts.Render("~/bundles/bootstrap")
#RenderSection("scripts", required: false)
</body>
</html>
Note how the scripts section is rendered last in the master layout file.

It means that your jQuery library has not been loaded yet.
You can move your code after pulling jQuery library.
or you can use something like this
window.onload = function(){
// Your code here
// $(".some-class").html("some html");
};

As stated above, it happens due to the conflict of $ variable.
I resolved this issue by reserving a secondary variable for jQuery with no conflict.
var $j = jQuery.noConflict();
and then use it anywhere
$j( "div" ).hide();
more details can be found here

make sure you really load jquery
this is not jquery - it's the ui!
<script language="JavaScript"
src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.10.0/jquery-ui.min.js">
</script>
This is a correct script source for jquery:
<script language="JavaScript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>

Are you using any other JavaScript libraries? If so, you will probably need to use jQuery in compatibility mode:
http://docs.jquery.com/Using_jQuery_with_Other_Libraries

after some tests i found a fast solution ,
you can add in top of your index page:
<script>
$=jQuery;
</script>
it work very fine :)

I had the same problem and resolved it by using
document.addEventListener('DOMContentLoaded', () => {
// code here
});

I got the same error message when I misspelled the jQuery reference and instead of type="text/javascript" I typed "...javascirpt". ;)

It sounds like jQuery isn't loading properly. Which source/version are you using?
Alternatively, it could a be namespace collision, so try using jQuery explicitly instead of using $. If that works, you may like to use noConflict to ensure the other code that's using $ doesn't break.

That error means that jQuery has not yet loaded on the page. Using $(document).ready(...) or any variant thereof will do no good, as $ is the jQuery function.
Using window.onload should work here. Note that only one function can be assigned to window.onload. To avoid losing the original onload logic, you can decorate the original function like so:
originalOnload = window.onload;
window.onload = function() {
if (originalOnload) {
originalOnload();
}
// YOUR JQUERY
};
This will execute the function that was originally assigned to window.onload, and then will execute // YOUR JQUERY.
See https://en.wikipedia.org/wiki/Decorator_pattern for more detail about the decorator pattern.

I use Url.Content and never have a problem.
<script src="<%= Url.Content ("~/Scripts/jquery-1.4.1.min.js") %>" type="text/javascript"></script>

In the solution it is mentioned -
"One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described."
For avoiding this -
Many JavaScript libraries use $ as a function or variable name, just as jQuery does. In jQuery's case, $ is just an alias for jQuery, so all functionality is available without using $. If we need to use another JavaScript library alongside jQuery, we can return control of $ back to the other library with a call to $.noConflict():

I had this problem once for no apparent reason. It was happenning locally whilst I was running through the aspnet development server. It had been working and I reverted everything to a state where it had previously been working and still it didn't work. I looked in the chrome debugger and the jquery-1.7.1.min.js had loaded without any problems. It was all very confusing. I still don't know what the problem was but closing the browser, closing the development server and then trying again sorted it out.

Just place jquery url on the top of your jquery code
like this--
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>

I had the same problem and it was because my reference to the jQuery.js was not in the tag. Once I switched that, everything started working.
Anthony

Check the exact path of your jquery file is included.
<script src="assets/plugins/jquery/jquery.min.js"></script>
if you add this on bottom of your page , please all call JS function below this declaration.
Check using this code test ,
<script type="text/javascript">
/***
* Created by dadenew
* Submit email subscription using ajax
* Send email address
* Send controller
* Recive response
*/
$(document).ready(function() { //you can replace $ with Jquery
alert( 'jquery working~!' );
});
Peace!

This is the common issue to resolve this you have to check some point
Include Main Jquery Library
Check Cross-Browser Issue
Add Library on TOP of the jquery code
Check CDNs might be blocked.
Full details are given in this blog click here

I came across same issue, and it resolved by below steps.
The sequence of the scripts should be as per mentioned below
<script src="~/Scripts/jquery-3.3.1.min.js"></script>
<script src="~/Scripts/jquery-ui.js"></script>
<script src="~/Scripts/bootstrap.min.js"></script>
This sequence was not correct for my code, I corrected this as per the above and it resolved my issue of Jquery not defined.

We have the same problem....but accidentally i checked folder properties and set something...
You have to check the properties of each folders that you're accessing..
right click folder
'permissions' tab
set the folder access :
OWNER: create and delete files
GROUP: access files
OTHERS: access files
I hope that this is the solution......

When using jQuery in asp.net, if you are using a master page and you are loading the jquery source file there, make sure you have the header contentplaceholder after all the jquery script references.
I had a problem where any pages that used that master page would return '$ is not defined' simply because the incorrect order was making the client side code run before the jquery object was created. So make sure you have:
<head runat="server">
<script type="text/javascript" src="Scripts/jquery-VERSION#.js"></script>
<asp:ContentPlaceHolder id="Header" runat="server"></asp:ContentPlaceHolder>
</head>
That way the code will run in order and you will be able to run jQuery code on the child pages.

In my case I was pointing to Google hosted JQuery. It was included properly, but I was on an HTTPS page and calling it via HTTP. Once I fixed the problem (or allowed insecure content), it fired right up.

After tried everything here with no result, I solved the problem simply by moving the script src tag from body to head

I was having this same problem and couldn't figure out what was causing it. I recently converted my HTML files from Japanese to UTF-8, but I didn't do anything with the script files. Somehow jquery-1.10.2.min.js became corrupted in this process (I still have no idea how). Replacing jquery-1.10.2.min.js with the original fixed it.

it appears that if you locate your jquery.js files under the same folder or in some subfolders where your html file is, the Firebug problem is solved. eg if your html is under C:/folder1/, then your js files should be somewhere under C:/folder1/ (or C:/folder1/folder2 etc) as well and addressed accordingly in the html doc. hope this helps.

I have the same issue and no case resolve me the problem. The only thing that works for me, it's put on the of the Site.master file, the next:
<script src="<%= ResolveUrl("~/Scripts/jquery-1.7.1.min.js") %>" type="text/javascript"></script>
<script src="<%= ResolveUrl("~/Scripts/bootstrap/js/bootstrap.min.js") %>" type="text/javascript"></script>
With src="<%= ResolveUrl("")... the load of jQuery in the Content Pages is correct.

$ is not defined referenceError JS Form submission [duplicate]

I have a simple jquery click event
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>
and a jquery reference defined in the site.master
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
I have checked that the script is being resolved correctly, I'm able to see the markup and view the script directly in firebug, so I must be being found. However, I am still getting:
$ is not defined
and none of the jquery works. I've also tried the various variations of this like $(document).ready and jQuery etc.
It's an MVC 2 app on .net 3.5, I'm sure I'm being really dense, everywhere on google says to check the file is referenced correctly, which I have checked and checked again, please advise! :/

That error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may have overwritten the $ variable.
You have JavaScript running before the page is fully loaded, and as such, before jQuery is fully loaded.
First of all, ensure, what script is call properly, it should looks like
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
and shouldn't have attributes async or defer.
Then you should check the Firebug net panel to see if the file is actually being loaded properly. If not, it will be highlighted red and will say "404" beside it. If the file is loading properly, that means that the issue is number 2.
Make sure all jQuery javascript code is being run inside a code block such as:
$(document).ready(function () {
//your code here
});
This will ensure that your code is being loaded after jQuery has been initialized.
One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described.
Note: If you're loading code which does not require jQuery to run it does not need to be placed inside the jQuery ready handler. That code may be separated using document.readyState.

It could be that you have your script tag called before the jquery script is called.
<script type="text/javascript" src="js/script.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
This results as $ is not defined
Put the jquery.js before your script tag and it will work ;) like so:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript" src="js/script.js"></script>

First you need to make sure that jQuery script is loaded. This could be from a CDN or local on your website. If you don't load this first before trying to use jQuery it will tell you that jQuery is not defined.
<script src="jquery.min.js"></script>
This could be in the HEAD or in the footer of the page, just make sure you load it before you try to call any other jQuery stuff.
Then you need to use one of the two solutions below
(function($){
// your standard jquery code goes here with $ prefix
// best used inside a page with inline code,
// or outside the document ready, enter code here
})(jQuery);
or
jQuery(document).ready(function($){
// standard on load code goes here with $ prefix
// note: the $ is setup inside the anonymous function of the ready command
});
please be aware that many times $(document).ready(function(){//code here}); will not work.

If the jQuery plugin call is next to the </body>, and your script is loaded before that, you should make your code run after window.onload event, like this:
window.onload = function() {
//YOUR JQUERY CODE
}
`
so, your code will run only after the window load, when all assets have been loaded. In that point, the jQuery ($) will be defined.
If you use that:
$(document).ready(function () {
//YOUR JQUERY CODE
});
`
the $ isn't yet defined at this time, because it is called before the jQuery is loaded, and your script will fail on that first line on console.

I just did the same thing and found i had a whole lot of
type="text/javacsript"
So they were loading, but no further hint as to why it wasn't working. Needless to say, proper spelling fixed it.

Use a scripts section in the view and master layout.
Put all your scripts defined in your view inside a Scripts section of the view. This way you can have the master layout load this after all other scripts have been loaded. This is the default setup when starting a new MVC5 web project. Not sure about earlier versions.
Views/Foo/MyView.cshtml:
// The rest of your view code above here.
#section Scripts
{
// Either render the bundle defined with same name in BundleConfig.cs...
#Scripts.Render("~/bundles/myCustomBundle")
// ...or hard code the HTML.
<script src="URL-TO-CUSTOM-JS-FILE"></script>
<script type="text/javascript">
$(document).ready(function () {
// Do your custom javascript for this view here. Will be run after
// loading all the other scripts.
});
</script>
}
Views/Shared/_Layout.cshtml
<html>
<body>
<!-- ... Rest of your layout file here ... -->
#Scripts.Render("~/bundles/jquery")
#Scripts.Render("~/bundles/bootstrap")
#RenderSection("scripts", required: false)
</body>
</html>
Note how the scripts section is rendered last in the master layout file.

It means that your jQuery library has not been loaded yet.
You can move your code after pulling jQuery library.
or you can use something like this
window.onload = function(){
// Your code here
// $(".some-class").html("some html");
};

As stated above, it happens due to the conflict of $ variable.
I resolved this issue by reserving a secondary variable for jQuery with no conflict.
var $j = jQuery.noConflict();
and then use it anywhere
$j( "div" ).hide();
more details can be found here

make sure you really load jquery
this is not jquery - it's the ui!
<script language="JavaScript"
src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.10.0/jquery-ui.min.js">
</script>
This is a correct script source for jquery:
<script language="JavaScript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>

Are you using any other JavaScript libraries? If so, you will probably need to use jQuery in compatibility mode:
http://docs.jquery.com/Using_jQuery_with_Other_Libraries

after some tests i found a fast solution ,
you can add in top of your index page:
<script>
$=jQuery;
</script>
it work very fine :)

I had the same problem and resolved it by using
document.addEventListener('DOMContentLoaded', () => {
// code here
});

I got the same error message when I misspelled the jQuery reference and instead of type="text/javascript" I typed "...javascirpt". ;)

It sounds like jQuery isn't loading properly. Which source/version are you using?
Alternatively, it could a be namespace collision, so try using jQuery explicitly instead of using $. If that works, you may like to use noConflict to ensure the other code that's using $ doesn't break.

That error means that jQuery has not yet loaded on the page. Using $(document).ready(...) or any variant thereof will do no good, as $ is the jQuery function.
Using window.onload should work here. Note that only one function can be assigned to window.onload. To avoid losing the original onload logic, you can decorate the original function like so:
originalOnload = window.onload;
window.onload = function() {
if (originalOnload) {
originalOnload();
}
// YOUR JQUERY
};
This will execute the function that was originally assigned to window.onload, and then will execute // YOUR JQUERY.
See https://en.wikipedia.org/wiki/Decorator_pattern for more detail about the decorator pattern.

I use Url.Content and never have a problem.
<script src="<%= Url.Content ("~/Scripts/jquery-1.4.1.min.js") %>" type="text/javascript"></script>

In the solution it is mentioned -
"One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described."
For avoiding this -
Many JavaScript libraries use $ as a function or variable name, just as jQuery does. In jQuery's case, $ is just an alias for jQuery, so all functionality is available without using $. If we need to use another JavaScript library alongside jQuery, we can return control of $ back to the other library with a call to $.noConflict():

I had this problem once for no apparent reason. It was happenning locally whilst I was running through the aspnet development server. It had been working and I reverted everything to a state where it had previously been working and still it didn't work. I looked in the chrome debugger and the jquery-1.7.1.min.js had loaded without any problems. It was all very confusing. I still don't know what the problem was but closing the browser, closing the development server and then trying again sorted it out.

Just place jquery url on the top of your jquery code
like this--
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>

I had the same problem and it was because my reference to the jQuery.js was not in the tag. Once I switched that, everything started working.
Anthony

Check the exact path of your jquery file is included.
<script src="assets/plugins/jquery/jquery.min.js"></script>
if you add this on bottom of your page , please all call JS function below this declaration.
Check using this code test ,
<script type="text/javascript">
/***
* Created by dadenew
* Submit email subscription using ajax
* Send email address
* Send controller
* Recive response
*/
$(document).ready(function() { //you can replace $ with Jquery
alert( 'jquery working~!' );
});
Peace!

This is the common issue to resolve this you have to check some point
Include Main Jquery Library
Check Cross-Browser Issue
Add Library on TOP of the jquery code
Check CDNs might be blocked.
Full details are given in this blog click here

I came across same issue, and it resolved by below steps.
The sequence of the scripts should be as per mentioned below
<script src="~/Scripts/jquery-3.3.1.min.js"></script>
<script src="~/Scripts/jquery-ui.js"></script>
<script src="~/Scripts/bootstrap.min.js"></script>
This sequence was not correct for my code, I corrected this as per the above and it resolved my issue of Jquery not defined.

We have the same problem....but accidentally i checked folder properties and set something...
You have to check the properties of each folders that you're accessing..
right click folder
'permissions' tab
set the folder access :
OWNER: create and delete files
GROUP: access files
OTHERS: access files
I hope that this is the solution......

When using jQuery in asp.net, if you are using a master page and you are loading the jquery source file there, make sure you have the header contentplaceholder after all the jquery script references.
I had a problem where any pages that used that master page would return '$ is not defined' simply because the incorrect order was making the client side code run before the jquery object was created. So make sure you have:
<head runat="server">
<script type="text/javascript" src="Scripts/jquery-VERSION#.js"></script>
<asp:ContentPlaceHolder id="Header" runat="server"></asp:ContentPlaceHolder>
</head>
That way the code will run in order and you will be able to run jQuery code on the child pages.

In my case I was pointing to Google hosted JQuery. It was included properly, but I was on an HTTPS page and calling it via HTTP. Once I fixed the problem (or allowed insecure content), it fired right up.

After tried everything here with no result, I solved the problem simply by moving the script src tag from body to head

I was having this same problem and couldn't figure out what was causing it. I recently converted my HTML files from Japanese to UTF-8, but I didn't do anything with the script files. Somehow jquery-1.10.2.min.js became corrupted in this process (I still have no idea how). Replacing jquery-1.10.2.min.js with the original fixed it.

it appears that if you locate your jquery.js files under the same folder or in some subfolders where your html file is, the Firebug problem is solved. eg if your html is under C:/folder1/, then your js files should be somewhere under C:/folder1/ (or C:/folder1/folder2 etc) as well and addressed accordingly in the html doc. hope this helps.

I have the same issue and no case resolve me the problem. The only thing that works for me, it's put on the of the Site.master file, the next:
<script src="<%= ResolveUrl("~/Scripts/jquery-1.7.1.min.js") %>" type="text/javascript"></script>
<script src="<%= ResolveUrl("~/Scripts/bootstrap/js/bootstrap.min.js") %>" type="text/javascript"></script>
With src="<%= ResolveUrl("")... the load of jQuery in the Content Pages is correct.

Not able to hide div using Jquery [duplicate]

I have a simple jquery click event
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>
and a jquery reference defined in the site.master
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
I have checked that the script is being resolved correctly, I'm able to see the markup and view the script directly in firebug, so I must be being found. However, I am still getting:
$ is not defined
and none of the jquery works. I've also tried the various variations of this like $(document).ready and jQuery etc.
It's an MVC 2 app on .net 3.5, I'm sure I'm being really dense, everywhere on google says to check the file is referenced correctly, which I have checked and checked again, please advise! :/

That error can only be caused by one of three things:
Your JavaScript file is not being properly loaded into your page
You have a botched version of jQuery. This could happen because someone edited the core file, or a plugin may have overwritten the $ variable.
You have JavaScript running before the page is fully loaded, and as such, before jQuery is fully loaded.
First of all, ensure, what script is call properly, it should looks like
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
and shouldn't have attributes async or defer.
Then you should check the Firebug net panel to see if the file is actually being loaded properly. If not, it will be highlighted red and will say "404" beside it. If the file is loading properly, that means that the issue is number 2.
Make sure all jQuery javascript code is being run inside a code block such as:
$(document).ready(function () {
//your code here
});
This will ensure that your code is being loaded after jQuery has been initialized.
One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described.
Note: If you're loading code which does not require jQuery to run it does not need to be placed inside the jQuery ready handler. That code may be separated using document.readyState.

It could be that you have your script tag called before the jquery script is called.
<script type="text/javascript" src="js/script.js"></script>
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
This results as $ is not defined
Put the jquery.js before your script tag and it will work ;) like so:
<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
<script type="text/javascript" src="js/script.js"></script>

First you need to make sure that jQuery script is loaded. This could be from a CDN or local on your website. If you don't load this first before trying to use jQuery it will tell you that jQuery is not defined.
<script src="jquery.min.js"></script>
This could be in the HEAD or in the footer of the page, just make sure you load it before you try to call any other jQuery stuff.
Then you need to use one of the two solutions below
(function($){
// your standard jquery code goes here with $ prefix
// best used inside a page with inline code,
// or outside the document ready, enter code here
})(jQuery);
or
jQuery(document).ready(function($){
// standard on load code goes here with $ prefix
// note: the $ is setup inside the anonymous function of the ready command
});
please be aware that many times $(document).ready(function(){//code here}); will not work.

If the jQuery plugin call is next to the </body>, and your script is loaded before that, you should make your code run after window.onload event, like this:
window.onload = function() {
//YOUR JQUERY CODE
}
`
so, your code will run only after the window load, when all assets have been loaded. In that point, the jQuery ($) will be defined.
If you use that:
$(document).ready(function () {
//YOUR JQUERY CODE
});
`
the $ isn't yet defined at this time, because it is called before the jQuery is loaded, and your script will fail on that first line on console.

I just did the same thing and found i had a whole lot of
type="text/javacsript"
So they were loading, but no further hint as to why it wasn't working. Needless to say, proper spelling fixed it.

Use a scripts section in the view and master layout.
Put all your scripts defined in your view inside a Scripts section of the view. This way you can have the master layout load this after all other scripts have been loaded. This is the default setup when starting a new MVC5 web project. Not sure about earlier versions.
Views/Foo/MyView.cshtml:
// The rest of your view code above here.
#section Scripts
{
// Either render the bundle defined with same name in BundleConfig.cs...
#Scripts.Render("~/bundles/myCustomBundle")
// ...or hard code the HTML.
<script src="URL-TO-CUSTOM-JS-FILE"></script>
<script type="text/javascript">
$(document).ready(function () {
// Do your custom javascript for this view here. Will be run after
// loading all the other scripts.
});
</script>
}
Views/Shared/_Layout.cshtml
<html>
<body>
<!-- ... Rest of your layout file here ... -->
#Scripts.Render("~/bundles/jquery")
#Scripts.Render("~/bundles/bootstrap")
#RenderSection("scripts", required: false)
</body>
</html>
Note how the scripts section is rendered last in the master layout file.

It means that your jQuery library has not been loaded yet.
You can move your code after pulling jQuery library.
or you can use something like this
window.onload = function(){
// Your code here
// $(".some-class").html("some html");
};

As stated above, it happens due to the conflict of $ variable.
I resolved this issue by reserving a secondary variable for jQuery with no conflict.
var $j = jQuery.noConflict();
and then use it anywhere
$j( "div" ).hide();
more details can be found here

make sure you really load jquery
this is not jquery - it's the ui!
<script language="JavaScript"
src="http://ajax.googleapis.com/ajax/libs/jqueryui/1.10.0/jquery-ui.min.js">
</script>
This is a correct script source for jquery:
<script language="JavaScript" src="http://ajax.googleapis.com/ajax/libs/jquery/1.10.0/jquery.min.js"></script>

Are you using any other JavaScript libraries? If so, you will probably need to use jQuery in compatibility mode:
http://docs.jquery.com/Using_jQuery_with_Other_Libraries

after some tests i found a fast solution ,
you can add in top of your index page:
<script>
$=jQuery;
</script>
it work very fine :)

I had the same problem and resolved it by using
document.addEventListener('DOMContentLoaded', () => {
// code here
});

I got the same error message when I misspelled the jQuery reference and instead of type="text/javascript" I typed "...javascirpt". ;)

It sounds like jQuery isn't loading properly. Which source/version are you using?
Alternatively, it could a be namespace collision, so try using jQuery explicitly instead of using $. If that works, you may like to use noConflict to ensure the other code that's using $ doesn't break.

That error means that jQuery has not yet loaded on the page. Using $(document).ready(...) or any variant thereof will do no good, as $ is the jQuery function.
Using window.onload should work here. Note that only one function can be assigned to window.onload. To avoid losing the original onload logic, you can decorate the original function like so:
originalOnload = window.onload;
window.onload = function() {
if (originalOnload) {
originalOnload();
}
// YOUR JQUERY
};
This will execute the function that was originally assigned to window.onload, and then will execute // YOUR JQUERY.
See https://en.wikipedia.org/wiki/Decorator_pattern for more detail about the decorator pattern.

I use Url.Content and never have a problem.
<script src="<%= Url.Content ("~/Scripts/jquery-1.4.1.min.js") %>" type="text/javascript"></script>

In the solution it is mentioned -
"One final thing to check is to make sure that you are not loading any plugins before you load jQuery. Plugins extend the "$" object, so if you load a plugin before loading jQuery core, then you'll get the error you described."
For avoiding this -
Many JavaScript libraries use $ as a function or variable name, just as jQuery does. In jQuery's case, $ is just an alias for jQuery, so all functionality is available without using $. If we need to use another JavaScript library alongside jQuery, we can return control of $ back to the other library with a call to $.noConflict():

I had this problem once for no apparent reason. It was happenning locally whilst I was running through the aspnet development server. It had been working and I reverted everything to a state where it had previously been working and still it didn't work. I looked in the chrome debugger and the jquery-1.7.1.min.js had loaded without any problems. It was all very confusing. I still don't know what the problem was but closing the browser, closing the development server and then trying again sorted it out.

Just place jquery url on the top of your jquery code
like this--
<script src="<%=ResolveUrl("~/Scripts/jquery-1.3.2.js")%>" type="text/javascript"></script>
<script type="text/javascript">
$(function() {
$('#post').click(function() {
alert("test");
});
});
</script>

I had the same problem and it was because my reference to the jQuery.js was not in the tag. Once I switched that, everything started working.
Anthony

Check the exact path of your jquery file is included.
<script src="assets/plugins/jquery/jquery.min.js"></script>
if you add this on bottom of your page , please all call JS function below this declaration.
Check using this code test ,
<script type="text/javascript">
/***
* Created by dadenew
* Submit email subscription using ajax
* Send email address
* Send controller
* Recive response
*/
$(document).ready(function() { //you can replace $ with Jquery
alert( 'jquery working~!' );
});
Peace!

This is the common issue to resolve this you have to check some point
Include Main Jquery Library
Check Cross-Browser Issue
Add Library on TOP of the jquery code
Check CDNs might be blocked.
Full details are given in this blog click here

I came across same issue, and it resolved by below steps.
The sequence of the scripts should be as per mentioned below
<script src="~/Scripts/jquery-3.3.1.min.js"></script>
<script src="~/Scripts/jquery-ui.js"></script>
<script src="~/Scripts/bootstrap.min.js"></script>
This sequence was not correct for my code, I corrected this as per the above and it resolved my issue of Jquery not defined.

We have the same problem....but accidentally i checked folder properties and set something...
You have to check the properties of each folders that you're accessing..
right click folder
'permissions' tab
set the folder access :
OWNER: create and delete files
GROUP: access files
OTHERS: access files
I hope that this is the solution......

When using jQuery in asp.net, if you are using a master page and you are loading the jquery source file there, make sure you have the header contentplaceholder after all the jquery script references.
I had a problem where any pages that used that master page would return '$ is not defined' simply because the incorrect order was making the client side code run before the jquery object was created. So make sure you have:
<head runat="server">
<script type="text/javascript" src="Scripts/jquery-VERSION#.js"></script>
<asp:ContentPlaceHolder id="Header" runat="server"></asp:ContentPlaceHolder>
</head>
That way the code will run in order and you will be able to run jQuery code on the child pages.

In my case I was pointing to Google hosted JQuery. It was included properly, but I was on an HTTPS page and calling it via HTTP. Once I fixed the problem (or allowed insecure content), it fired right up.

After tried everything here with no result, I solved the problem simply by moving the script src tag from body to head

I was having this same problem and couldn't figure out what was causing it. I recently converted my HTML files from Japanese to UTF-8, but I didn't do anything with the script files. Somehow jquery-1.10.2.min.js became corrupted in this process (I still have no idea how). Replacing jquery-1.10.2.min.js with the original fixed it.

it appears that if you locate your jquery.js files under the same folder or in some subfolders where your html file is, the Firebug problem is solved. eg if your html is under C:/folder1/, then your js files should be somewhere under C:/folder1/ (or C:/folder1/folder2 etc) as well and addressed accordingly in the html doc. hope this helps.

I have the same issue and no case resolve me the problem. The only thing that works for me, it's put on the of the Site.master file, the next:
<script src="<%= ResolveUrl("~/Scripts/jquery-1.7.1.min.js") %>" type="text/javascript"></script>
<script src="<%= ResolveUrl("~/Scripts/bootstrap/js/bootstrap.min.js") %>" type="text/javascript"></script>
With src="<%= ResolveUrl("")... the load of jQuery in the Content Pages is correct.

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