Uncaught ReferenceError: $ is not defined?

问题

How come this code throws an

Uncaught ReferenceError: $ is not defined

when it was OK before?

$(document).ready(function() {
    $('#tabs > ul').tabs({ fx: { opacity: 'toggle' } });
    $('#featuredvid > ul').tabs();
});

Results in tabs don't close anymore.

jQuery is referenced in the header:

<script language="JavaScript" type="text/javascript" src="<?php echo get_option('siteurl') ?>/js/sprinkle.js"></script>
<script language="JavaScript" type="text/javascript" src="<?php echo get_option('siteurl') ?>/js/jquery-1.2.6.min.js"></script>
<script language="JavaScript" type="text/javascript" src="<?php echo get_option('siteurl') ?>/js/jquery-ui-personalized-1.5.2.packed.js"></script>

回答1:

You should put the references to the jquery scripts first.

<script language="JavaScript" type="text/javascript" src="/js/jquery-1.2.6.min.js"></script>
<script language="JavaScript" type="text/javascript" src="/js/jquery-ui-personalized-1.5.2.packed.js"></script>
<script language="JavaScript" type="text/javascript" src="/js/sprinkle.js"></script>

回答2:

You are calling the ready function before the jQuery JavaScript is included. Reference jQuery first.

回答3:

This is what solved it for me. Originally I went to Google and copied and pasted their suggested snippet for jQuery on their CDN page:

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>

The snippet does not include the HTTP: or HTTPS: in the src attribute but my browser, FireFox, needed it so I changed it to: edit: this worked for me with Google Chrome as well

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>

Then it worked.

回答4:

If your custom script is loaded before the jQuery plugin is loaded to the browser then this type of problem may occur. So, always keep your own JavaScript or jQuery code after calling the jQuery plugin so the solution for this is :

First add the link to the jQuery file hosted at GoogleApis or a local jQuery file that you will download from http://jquery.com/download/ and host on your server:

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>

or any plugin for jQuery. Then put your custom script file link or code:

<script src="js/custom.js" type="text/javascript"></script>

回答5:

In my case I was putting my .js file before the jQuery script link, putting the .js file after jQuery script link solved my issue.

<script src="http://code.jquery.com/jquery-1.10.2.js"></script>
<script src="http://code.jquery.com/ui/1.11.2/jquery-ui.js"></script>
<script src="http://maxcdn.bootstrapcdn.com/bootstrap/3.2.0/js/bootstrap.min.js"></script>
<script src="exponential.js"></script>

回答6:

Okay, my problem was different - it was Document Security model in Chrome.

Looking at the answers here, it was obvious that I was somehow not loading my jquery files before calling the $(document).ready() etc. functions. However, they were all in the correct positions.

In my case, this was because I was accessing the content over a secure HTTPS connection, whereas the page was trying to download the CDN hosted data from google, etc. The solution was to store them locally and then include then directly rather than from the CDN each time.

Edit: The other way of doing this is to link to all the CDN-hosted stuff as https:// rather than http:// - then the model doesn't complain.

回答7:

Add the library before you start the script.You can add any of these following CDN to start it.

Google:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.2.1/jquery.min.js"></script>

Microsoft

<script src="https://ajax.aspnetcdn.com/ajax/jQuery/jquery-3.2.1.min.js"></script>

Jquery

If you want any other Jquery cdn version check this link.

After this:

<script type="text/javascript">
$(function(){
    //your stuff
});
or
$(document).ready(function(){
    //your stuff
});    
</script>

Wordpress:

<script type="text/javascript">
var $ = jQuery;
jQuery(document).ready(function($){
     //your stuff
});
</script>

回答8:

If it's in wordpress, might be needed to change

$(document).ready(function() {

jQuery(document).ready(function($){

or add

var $ = jQuery;

before

$(document).ready(function() {

回答9:

I had the exact same problem and none of these solutions above helped. however, I just linked the .css files after the .js files and the problem miraculously disappeared. Hope this helps.

回答10:

I wanted to try to make my script asynchronous. Then I forgot about it and when I went live the [custom].js file only loaded 50% of the time before the jQuery.js.

So I changed

<script async src="js/script.js"></script>

<script src="js/script.js"></script>

回答11:

In my case I had this referenceError as the order of script calls was wrong. Solved that by changing the order:

<script src="js/index.js"></script>
<script src="js/jquery-1.10.2.js"></script>

<script src="js/jquery-1.10.2.js"></script>
<script src="js/index.js"></script>

回答12:

I had the same problem , and I solved by putting jQuery at the top of all javascript codes I have in my code.

Something like this:

<script src="https://code.jquery.com/jquery-3.3.1.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0/js/bootstrap.min.js"></script>
<script src="js/app.js" type="text/javascript"></script>
<script src="js/form.js" type="text/javascript"></script>
<script src="js/create.js" type="text/javascript"></script>
<script src="js/tween.js" type="text/javascript"></script>

Hope can help some one in future.

回答13:

You are calling the ready() function before the jQuery JavaScript is included. Reference jQuery first.

If you're in ASP.NET MVC, you can specify when your JS code should be rendered, by doing this:

1, In your page.cshtml wrap your <script> tag into a section, and give it a name, the common name to use is 'scripts':

@section scripts {
    <script>
        // JS code...
    </script>
}

2, In your _Layout.cshtml page add @RenderSection("Scripts", required: false), make sure to put it after you reference the Jquery source, this will make your JS code render later than the Jquery.

回答14:

If you are doing this in .Net and have the script file referenced properly and you jQuery looks fine, make sure that your users have access to the script file. The project I was working on (a coworker) had their web.config denying access to anonymous users. The page I was working on was accessible to anonymous users therefore they didn't have access to the script file. Dropped the following into the web.config and all was right in the world:

  <location path="Scripts">
    <system.web>
      <authorization>
        <allow users="*"/>
      </authorization>
    </system.web>
  </location>

回答15:

The source file jquery-1.2.6.min.js is not called the jQuery command $() is executed earlier than <..src='jquery-1.2.6.min.js'>.

Please run <.. src="/js/jquery-1.2.6.min.js.."> at first and make sure the src path is right, then execute jquery command

$(document).ready(function()

回答16:

This happened to me before.

The reason was that I'm connecting android to a webview with a JS. And I sent a parameter without quotes.

js.sayHello(hello);

and when I changed it to

js.sayHello('hello');

it worked.

回答17:

In my case it was a typo, I forgot a backslash and was referencing the source incorrectly.

Before src="/scripts/jquery.js"

After src="scripts/jquery.js"

回答18:

Your JavaScript file is missing so this error occurred. Just add the JavaScript file inside the <head> tag. See the example:

<script src="js/sample.js" type="text/javascript"></script>
<link href="css/sample.css" rel="stylesheet" type="text/css" />

or add the following code in tag :

<script src="http://ajax.googleapis.com/ajax/libs/jquery/1.9.1/jquery.min.js"></script>

回答19:

The error will occur in the following two scenarios as well.

@section scripts element is missing from the HTML file
Error in accessing DOM elements. For example accessing of DOM element is mentioned as $("js-toggle") instead of $(".js-toggle"). Actually the period is missing

So 3 things to be followed - check required scripts are added, check if it is added in the required order and third syntax errors in your Java Script.

回答20:

Doh! I had mixed quotes in my tags that caused the jquery reference to break. Doing an inspect in Chrome allowed me to see that the file wasn't properly linked.

回答21:

In my case i forgot to include this :

 <script src ="jquery-2.1.1.js"></script>

Earlier I was including just jquery-mobile which was causing this error.

回答22:

I modified the script tag to point to the right content and changed the script order to be the right one in the editor. But totally forgot to save the change.

回答23:

I had a similar issue and it was because I was missing a closing > on a style sheet link.

回答24:

<script src="https://ajax.googleapis.com/ajax/libs/jquery/2.1.4/jquery.min.js"></script>
<script type="text/javascript" src="local_xxx.js"></script>

I have similar issue, and you know what, it's because of network is disconnected when I test in android device webview and I don't realize it, and the local js no problem to load because it doesn't need network. It seems ridiculous but it waste my ~1 hour to figure out it.

回答25:

Strange enough, my problem was coming from PHP.

A REST API call was failing, and it was breaking the loading of the libraries afterwards. Since failure was from the REST call, it was not giving me a php compile error.

Keep this as an option also, if loading jquery seems ok.

回答26:

I had this issue, when I was browsing internet through my mobile hotspot. it was also compressing images and added the following script at the bottom of body tag

<script language="javascript"><!--
bmi_SafeAddOnload(bmi_load,"bmi_orig_img");//-->
</script>

When I connected to proper wifi connection, all seems to work find for me. Hope this help someone.

回答27:

I had similar issue. My test server was working fine with "http". However it failed in production which had SSL.

Thus in production, I added "HTPPS" instead of "HTTP" and in test, i kept as it is "HTTP".

Test:

wp_register_script( 'jquery', 'http://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js', array(), null, false );

wp_register_script( 'custom-script', plugins_url( '/js/custom.js', FILE ), array( 'jquery' ) );

Production:

wp_register_script( 'jquery', 'https://ajax.googleapis.com/ajax/libs/jquery/1.11.2/jquery.min.js', array(), null, false );

wp_register_script( 'custom-script', plugins_url( '/js/custom.js', FILE ), array( 'jquery' ) );

Hope this will help someone who is working on wordpress.

回答28:

This can also happen, if there is network issue. Which means, that even though the " jquery scripts " are in place, and are included prior to usage, since the jquery-scripts are not accessible, at the time of loading the page, hence the definitions to the "$" are treated as "undefined references".

FOR TEST/DEBUG PURPOSES :: You can try to access the "jquery-script" url on browser. If it is accessible, your page, should load properly, else it will show the said error (or other script relevant errors). Example - http://ajax.googleapis.com/ajax/libs/jquery/1.7.2/jquery.min.js should be accessible, on the browser (or browser context stances).

I had similar problem, in which I was able to load the html-page (using scripts) in my windows-host-browser, but was not able to load in vm-ubuntu. Solving the network issue, got the issue resolved.

回答29:

var $ = jQuery;
jQuery(document).ready(function($){

回答30:

Root problem is a ReferenceError. MDN indicates that a try/catch block is the proper tool for the job. In my case, I was getting uncaught reference error for a payment sdk/library. The below works for me.

try {
  var stripe = Stripe('pk_test_---------');
} catch (e) {
    stripe = null;
}

if(stripe){
  //we are good to go now
}

Obviously the fix is to load whatever SDK/library, e.g. jQuery, prior to calling its methods but the try/catch does keep your shared JavaScript from barfing up errors in case you run that shared script on a page that doesn't load whatever library you use on a subset of pages.

来源：https://stackoverflow.com/questions/43061310/is-not-defined-in-sugarcrm

标签

javascript

jquery

referenceerror