Refresh image in js

The Image object also supports the standard properties and events. If you want to report an error, or if you want to make a suggestion, do not hesitate to send us an e-mail:.

HOW TO. Your message has been sent to W3Schools.

refresh image in js

W3Schools is optimized for learning, testing, and training. Examples might be simplified to improve reading and basic understanding. Tutorials, references, and examples are constantly reviewed to avoid errors, but we cannot warrant full correctness of all content.

While using this site, you agree to have read and accepted our terms of usecookie and privacy policy. Copyright by Refsnes Data. All Rights Reserved. Powered by W3. Not supported in HTML5. Use style. Sets or returns the value of the align attribute of an image. Sets or returns the value of the border attribute of an image. Sets or returns the value of the hspace attribute of an image. Sets or returns the value of the longdesc attribute of an image.

Sets or returns a URL to a low-resolution version of an image. Use id instead. Sets or returns the value of the name attribute of an image. Sets or returns the value of the vspace attribute of an image.I would like to display an image call it "Image. PNG" on a html web page and could use javascript. Are you looking to change the entire image and then be stable while the user is viewing the page? If so, can you just append a random number to the filename in the script?

And then set a meta tag refresh on the html page to refresh at a set interval? Thank you everyone. Sorry for the delay, I was taken away from this project for a while and now I'm looking into it again. I would like to have the image change. I would like the page to be stable and if possible not flicker. Optimally I would like to eliminate flicker. I am open to creative options in regards to that, such as fade from one version of the image to a new one, or fade to black and then to the new image, etc.

Thank you for pointing me in this direction. I did look into this system but for our needs it is a little outside the scope. I'm not sure if it is me or what but the refresh was not working with this code. I had read about that issue and that solution which is very interesting. However I was actually just looking for a method to have the webpage refresh at a set interval with minimum screen flicker and minimum code.

refresh image in js

I just noticed a typo in the code above, semicolon at the end of line 6, looks like spiceworks code formatter put it there as I can't remove it. But even with typo, code works for me. OK so i went back and tested it again this time with IE and firefox and they both work. Chrome is not refreshing. Thank you for your assistance. I am going to see if I can adjust the jQuery to fade in on reloads?

To continue this discussion, please ask a new question. Get answers from your peers along with millions of IT pros who visit Spiceworks. I am looking for the best solution to the following: I would like to display an image call it "Image. I would like to update the image when there are changes. The image file is dynamically generate and is always the same file name. I would like there to be no flicker. Your help is much appreciated. Popular Topics in Web Development. Spiceworks Help Desk.

The help desk software for IT. Track users' IT needs, easily, and with only the features you need. Ghost Chili. I'm not sure, but are you looking for a digital signage solution?

Xibo free and BrightSign paid are two we use here Alene Jul 26, at UTC.To reduce loading times and unexpected behavior, it can be desirable to load images into the browser's cache as soon as a page is loaded, especially when those images will not be needed right away. This page explains how to use JavaScript to load images into the browser's cache. One of the built-in object types in JavaScript is the Image object.

This object can be used to represent an HTML image tag on the page. The following code demonstrates how to create a JavaScript Image object:. The image object created above is empty. It has no image file associated with it. To load an image into the object, simply update the code as follows:.

As a result, that image has now been loaded into the browser's cache. To demonstrate the preloading of the image, I will use the following code. This code creates an empty image object, then allows the user to press a button to load the image. The image in this example is 6. Using the onload image event, a function will be called as soon as the image has finished loading, notifying the user that the image has been loaded into the cache.

Once an image is preloaded with JavaScript, you can take advantage of the cached image using only its filename.

Auto-Refresh Specific HTML Section: using jQuery

It's not necessary to keep using the JavaScript variable that you loaded the image into. To demonstrate this, I wrote the following code.

First, you can press a button to preload the image. After it has finished loading, the page displays a button that allows you to use the preloaded image in an image tag, using only the image filename. Even though we aren't using the variable that we loaded the image into, the image will still show up right away because it's in the cache.

Toggle navigation. Preloading Images with JavaScript To reduce loading times and unexpected behavior, it can be desirable to load images into the browser's cache as soon as a page is loaded, especially when those images will not be needed right away. Get help with games!

Go to list of all games.I have a webcam page that just shows a captured JPG that is updated every 10 seconds. Currently I am having the whole page refresh every 10 seconds, but that uses more bandwidth and jumps the viewer back to the top of the page every time it refreshes. Then you can set a Refresh tag in the head of that document, leaving the outer document alone. You may be able to do this with Javascript as well although I haven't tested it.

Good luck! Oh, just to clarify, the line obj. At least, that's the theory behind it! Am I thinking wrong or is that basically it???? I think I'm right. I'll let you know if it works What does the "? The "? Essentially, he's passing random numbers to tell the server "Hey! I want the image, and I want to tell you xxxxx" It forces the server to adhere to the possiblity that the image is not always the same, and therefore must be loaded anew and not from the cache.

Anywhere will work. Just curious. Sorry, I guess I was a bit too vague This would work in really old browsers too. It's Javascript. Or Jscript. Only gets the new image from the server when your javascript timer goes off in this case every 5 seconds [ ms]. Very slick I don't have anything constructive to add and other people have already solved your problembut this really pisses me off.

I get the point. On a side note, it says something troubling about your personality that something this trivial could "really [piss you] off". I promise to never capitalise it again if you promise to spend some time in meditation and prayer. Ars Tribunus Militum et Subscriptor.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information.

The issue I am running into is that if I try to load the image in the background and then update the one on the page, the image doesn't change--though it is updated when I reload the page. This will append the current timestamp automatically when you are creating the image, and it will make the browser look again for the image instead of retrieving the one in the cache.

I've seen a lot of variation in answers for how to do this, so I thought I'd summarize them here plus add a 4th method of my own invention :. Cons: Bypasses caching altogether, meaning unnecessary delays and bandwidth use whenever the image doesn't change between views.

Will potentially fill browser cache and any intermediate caches with many, many copies of exactly the same image! Also, requires modifying image URL. When to use: Use when image is constantly changing, such as for a live webcam feed. If you use this method, make sure to serve the images themselves with Cache-control: no-cache HTTP headers!!!

Often this can be set up using a. Otherwise you'll be progressively filling caches up with old versions of the image! That's PHP server-side code, but the important point here is just that a? Cons: Requires modifying the image URL.

Also, a little more work for the server - it has to get access to the file-last-modified time. Also, requires server-side information, so not suitable for a purely client-side-only solution to check for a refreshed image.

refresh image in js

When to use: When you want to cache images, but may need to update them at the server end from time to time without changing the filename itself. The idea here is that the cache-control header puts images in the browser cache, but immediately markes them stale, so that and every time they are re-displayed the browser must check with the server to see if they've changed. This ensures that the browser's HTTP cache always returns the latest copy of the image.

However, browsers will often re-use an in-memory copy of an image if they have one, and not even check their HTTP cache in that case.

refresh image in js

To prevent this, a fragment identifier is used: Comparison of in-memory image src 's includes the fragment identifier, but it gets stripped of before querying the HTTP cache. So, e. Works for servers that choke on a querystring added to a static image URL since servers never see fragment identifiers - they're for the browsers' own use only.

Refresh an image after an ajax file upload in jQuery

Cons: Relies on somewhat dubious or at least poorly documented behaviour of browsers, in regard to images with fragment identifiers in their URLs However, I've tested this successfully in FF27, Chrome33, and IEThe browser will view a file name of style. So, each time you update your CSS on the server, you can incrementally update your version number.

This will have no effect on the CSS. You could add many types of characters to the query string value, but numbers are a logical way to do it, because then you can just increase the number, and even add decimal places if you want. Of course. The tip is not just for dynamic server-driven pages. It should generally work to force the updating of any file, even an image file.

Secondly when you include a style sheet you will usually update a template so it forces your browser to look at the updated URL, with an HTML file best you can do is link to it and let people click through. This is recommended when the content changes a lot, such as AJAX requests or other dynamic content. This function returns the time when the data blocks of a file were being written to, that is, the time when the content of the file was changed.

Thank you sooo much! Please, read the article. My question is: How common are these proxy services? I often rename the file appending the current timestamp only when I make some change. Optimizing Cache — Leverage proxy caching. Good article! The project has a build script included, which updates the linked souces automatically.

This solves the caching issue. An alternative to the timestamp method as described above is to use the first seven characters of the md5 string of the css file:.

I think this method is cool to use automatic versioning instead of changing the version number every time. While using version numbers or even dates to bust old cached versions of a file, they are really not a good final solution to optimal cache control. You have go go one step beyond that. Version numbering requires manual updates and timestamps only work correctly under the assumption that you are working directly on the affected files, and not going through VCS, deployment scripts etc.

A better metod is to have a build step that renames the file itself to a hash of its content. This way the file name become an identifier of both the file and its content at the same time.

Most sites have a build step for minification and bundling anyway, just add this into the process.

Forcing an image refresh in HTML

This way you could for example build and deploy your new versions of static files into the same directory as the ones that are already in production.

They will just be there and be ready for being linked to by a new version of your html.GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together. Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community. Already on GitHub?

Sign in to your account. I am uploading an image in cropper container with the help of jquery. So I wrote a function to generate base64 string in my controller and assigned it to some other image tag which is not being used by cropper, It works fine for that but It is not working for image container in cropper.

Skip to content. Dismiss Join GitHub today GitHub is home to over 40 million developers working together to host and review code, manage projects, and build software together. Sign up. New issue. Jump to bottom. Copy link Quote reply. This comment has been minimized. Sign in to view. Restart the cropper or call the replace method to change image src.

How do I call the replace method? Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment. Linked pull requests. You signed in with another tab or window. Reload to refresh your session. You signed out in another tab or window.


Leave a Reply

Your email address will not be published. Required fields are marked *