How to Run a jQuery or JavaScript Before Page Start to Load
Question: setup_account ui-mobile-viewport ui-overlay-c When a page i make loads like this: I have multiple scripts running on the : I don’t know how to make this other JavaScripts run after page load. Pages are processed top to bottom so things at the top are processed first.
Load jQuery with Javascript and use jQuery
I am appending the jQuery library to the dom using:
How do I load jQuery dynamically as well as use it once it is in the dom?
There's a working JSFiddle with a small example here, that demonstrates exactly what you are looking for (unless I've misunderstood your request) : http://jsfiddle.net/9N7Z2/188/
There are a few issues with that method of loading javascript dynamically. When it comes to the very basal frameworks, like jQuery, you actually probably want to load them statically, because otherwise, you would have to write a whole JavaScript loading framework.
You could use some of the existing JavaScript loaders, or write your own by watching for window.jQuery to get defined.
// Immediately-invoked function expression (function() < // Load the script const script = document.createElement("script"); script.src = 'https://ajax.googleapis.com/ajax/libs/jquery/3.6.0/jquery.min.js'; script.type = 'text/javascript'; script.addEventListener('load', () => < console.log(`jQuery $has been loaded successfully!`); // use jQuery below >); document.head.appendChild(script); >)();
Just remember that if you need to support really old browsers, like IE8, load event handlers do not execute. In that case, you would need to poll for the existance of window.jQuery using repeated window.setTimeout . There is a working JSFiddle with that method here: http://jsfiddle.net/9N7Z2/3/
There are lots of people who have already done what you need to do. Check out some of the existing JavaScript Loader frameworks, like:
https://developers.google.com/loader/ (no longer documented)
http://yepnopejs.com/ (deprecated)
http://requirejs.org/
There is an other way to load jQuery dynamically (source). You could also use
It's considered bad practice to use document.write , but for sake of completion it's good to mention it.
See Why is document.write considered a "bad practice"? for the reasons. The pro is that document.write does block your page from loading other assests, so there is no need to create a callback function.
Encosia's website recommends:
But even he admits that it just doesn't compare to doing the following when it comes to optimal performance:
jQuery(document).ready(function()< // write here >);
suggestion : use live or bind
Jquery - Run javascript after page load, Unless you need javascript to do something before the page is loaded, add your scripts to the bottom om the html document, just before the body end tag. The page will load faster, and you can do whatever you need to, right in the js file, without the document ready functions.
Auto run Javascript on page load
I'm trying to run a piece of JavaScript automatically when a page loads. The code itself simply pops up a link to our self service portal.
I've attempted using onload and onclick with no success. Any help much appreciated.
jQuery.ready() Specifies a function to execute when the DOM is fully loaded.
Just include your JS file at the end of the document and execute your code.
Read more on my relevant blog post You Don't Need the DOM Ready event
Jquery - Auto run Javascript on page load, 3 Answers. jQuery.ready () Specifies a function to execute when the DOM is fully loaded. Just include your JS file at the end of the document and execute your code. Read more on my relevant blog post You Don't Need the DOM Ready event. $ (function () < console.log ('Page loaded!'); >);
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How to run Javascript code before document is completely loaded (using jQuery)
How to run Javascript code before document is completely loaded (using jQuery)
JQuery helps faster page load than javascript. JQuery functions are fired when the related elements are loaded, instead of complete pageload.
This is a common practice to call a javascript function when page is loaded like
window.onload = function() < alert(“Mindfire”) > or
Inside of which is the code that we want to run right when the page is loaded. Problematically, however, the Javascript code isn’t run until all images are finished downloading (this includes banner ads). The reason for using window.onload in the first place is due to the fact that the HTML ‘document’ isn’t finished loading yet, when you first try to run your code. To circumvent both problems, jQuery has a simple statement that checks the document and waits until it’s ready to be manipulated, known as the ready event
I faced a browser-related issue. Suppose we have some text field with size 100 along with some text area with same no of columns. In IE the size of text field and text area are same but in mozilla textarea will display with bigger length than text fields. This disturbs our layout and we want to resize this by detecting browser.
for mozilla we have to resize it as follows:
But problem is that the text area will resize after complete page load so when page loading is in process user will be able to view a wrong alignment and then the right one after complete page load.
With JQuery we can do this when a specific document element is loaded. For example, when the text area is loaded the related function will be fired, as given below.
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