Html not cache image

How to force a web browser not to cache images in Html?

When a web page is loaded, the browser stores certain resources, such as images, in a cache to improve the performance of subsequent page loads. However, in some cases, it may be necessary to prevent the browser from caching certain images. This can be useful in situations where the images are frequently updated and you want to ensure that the most recent version is always displayed to the user.

Method 1: Using HTTP Headers

To force a web browser not to cache images, you can use HTTP headers. Here’s how to do it:

1. Alternatively, you can use the Expires header to set a date in the past, which will force the browser to always request a new copy of the image:

1. If you’re using Apache, you can also use the mod_headers module to set the headers in your .htaccess file:

FilesMatch "\.(gif|jpg|jpeg|png)$"> Header set Cache-Control "no-cache, must-revalidate" Header set Expires "Mon, 26 Jul 1997 05:00:00 GMT" FilesMatch>

meta http-equiv="Cache-Control" content="no-cache, must-revalidate"> meta http-equiv="Expires" content="Mon, 26 Jul 1997 05:00:00 GMT">

By using these methods, you can ensure that the browser always requests a new copy of the image, rather than using a cached version.

Method 2: Using HTML Meta Tags

To force a web browser not to cache images using HTML Meta Tags, you can use the following code:

meta http-equiv="Cache-Control" content="no-cache, no-store, must-revalidate"> meta http-equiv="Pragma" content="no-cache"> meta http-equiv="Expires" content="0">

Here’s a brief explanation of each line:

1. Cache-Control specifies the caching behavior that the browser should follow. no-cache indicates that the browser should always revalidate the resource with the server before serving it, no-store indicates that the browser should not store a copy of the resource in its cache, and must-revalidate indicates that the browser must revalidate the resource with the server after it has expired.
2. Pragma is an HTTP/1.0 header that is used for backwards compatibility with older browsers. no-cache instructs the browser not to cache the resource.
3. Expires is an HTTP/1.0 header that specifies the date and time after which the resource is considered stale. A value of 0 indicates that the resource has already expired.

By including these meta tags in your HTML code, you can ensure that the browser always requests the latest version of the image from the server, and does not use a cached copy.

Method 3: Using JavaScript

To force a web browser not to cache images using JavaScript, you can add a unique parameter to the image URL. This will make the browser think that it is a new URL and it will not retrieve the image from cache. Here’s how you can do it:

var img = document.getElementById('myImage');

img.src = "path/to/image.png?nocache token operator">+ new Date().getTime();

1. The new Date().getTime() method will generate a unique number that will be added to the URL as a parameter. This will make the browser think that it is a new URL and it will not retrieve the image from cache.

var img = document.getElementById('myImage'); img.src = "path/to/image.png?nocache token operator">+ new Date().getTime();

You can also use the XMLHttpRequest object to fetch the image and set the cache-control header to no-cache . Here’s how you can do it:

var xhr = new XMLHttpRequest(); xhr.open('GET', 'path/to/image.png', true); xhr.setRequestHeader('cache-control', 'no-cache'); xhr.responseType = 'blob'; xhr.onload = function(e)  if (this.status == 200)  var blob = new Blob([this.response], type: 'image/png'>); var img = document.createElement('img'); img.src = window.URL.createObjectURL(blob); document.body.appendChild(img); > >; xhr.send();

In this code, we are using the XMLHttpRequest object to fetch the image and set the cache-control header to no-cache . We are also setting the responseType to blob so that we can create a new image element from the response. Finally, we are appending the image element to the document body.

These are two ways you can force a web browser not to cache images using JavaScript.

Method 4: Append a Unique Parameter in the Image URL

To force a web browser not to cache images, you can append a unique parameter in the image URL. Here’s how to do it:

img src="image.jpg?timestamp=123456789">

1. To make the timestamp unique every time the page is loaded, you can use a random number generator:

var timestamp = Date.now() + Math.floor(Math.random() * 1000000);

1. If you’re using a JavaScript framework like jQuery, you can use its $.ajax function to load the image and append the timestamp as a query parameter:

$.ajax( url: 'image.jpg', cache: false, data:  timestamp: Date.now() >, success: function(data)  $('body').append('+ data + '">'); > >);

By appending a unique parameter to the image URL, you can force the web browser to fetch the image from the server every time the page is loaded, instead of loading it from the cache.

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How to fix image not showing in an HTML page

Posted on Aug 11, 2021

There are two things you can do to fix an HTML image not showing up on the browser:

• Check the src path to of the tag
• Check the cache of the website on the production host

This tutorial will explain the above methods, starting with checking the src path

Check the src path to fix image not showing

Every image in HTML is rendered by using the tag with the image source specified in the src attribute.

You can put a relative path or an absolute path to the src attribute depending on where you place the image.

If your image is saved locally in a folder beside your HTML document location, then you can use the relative path.

Suppose you have the following folder structure in your project:

Then inside the index.html file, you can display the image using the following tag:

When your image is one folder down as in the following structure:

Then you need to add the folder assets to the src attribute as follows:

The relative path can also go up a folder by using the ../ pattern, so if you have the following structure:

The index.html file can reach the image using the following src attribute:

When you have the correct path, don’t forget to check the image extension and make sure it’s the same between the src and the actual image.

Sometimes an image with .png extension is written to the src attribute as .jpg extension.

Once the image src path is correct, then you need to check if the image is accessible by your server.

Keep in mind that if you use a local development server like XAMPP, WAMP, or MAMP, then the image must be located inside the development folder.

For WAMP, the image must be inside the www/ folder, while for XAMPP and MAMP you need to place the image inside the htdocs/ folder.

Finally, if you’re using an absolute path, make sure that you’re not placing your local hard disk path to the src attribute.

The following example will not work when you put the website online:

Once you’ve verified that the image is accessible in development, the image may still disappear from your production site because of the cache.

Let’s see how to clear the cache next.

Check the cache to fix image not showing

One reason for images not showing up on a website is because the browser or the server cache still serving the old HTML page to the visitors.

This only happens when you revise an already published HTML file to include a new image on the page.

Clearing browser cache may be different depending on the browser that you’re using.

If you’re using Chrome, then you can clear the cache by opening the developer tools menu and then right-click on the reload icon.

There, you can click on the Empty Cache and Hard Reload option:

The browser should refresh the page and pull the new page from your server.

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