How to Dynamically Display Images from a URL and Avoid Browser Caching?

Displaying Dynamic Images with URL Cached

Consider a scenario where you retrieve an image from a specific URL, ensuring that each access yields a unique image. However, when attempting to update the image on the page, the image remains unchanged unless the page is reloaded.

JavaScript Code for Image Display

The following JavaScript code illustrates the image display and refresh mechanism:

var newImage = new Image();
newImage.src = "http://localhost/image.jpg";

function updateImage() {
  if (newImage.complete) {
    document.getElementById("theText").src = newImage.src;
    newImage = new Image();
    newImage.src = "http://localhost/image/id/image.jpg?time=" + new Date();
  }

  setTimeout(updateImage, 1000);
}

In the given scenario, the image is not updating due to the potential for the browser to cache the image at the specified URL. This can prevent the browser from fetching the most recent image version.

Overcoming the Cache Problem

To force a refresh of the image, the URL can be appended with a cachebreaker. This will ensure that the browser fetches the image directly from the server instead of relying on the cached version. The amended code would include:

newImage.src = "http://localhost/image.jpg?" + new Date().getTime();

This addition ensures that the current timestamp is appended to the URL each time an image is created. As a result, the browser will retrieve the image from the server instead of accessing the cached version. By adding this cachebreaker, the image on the page will update dynamically, reflecting the latest version provided by the server.

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