How to prevent repeated display of images in HTML

In web design, it is often necessary to display multiple pictures on the page, but sometimes we need to prevent these pictures from being displayed repeatedly. In this case, we can use some attributes and techniques of HTML to achieve this. This article will introduce how to prevent repeated display of images in HTML.

1. Use the background attribute of CSS

In HTML, we can use CSS styles to set the background image of elements. And use the background-repeat attribute to control how the background image repeats. If set to no-repeat, the effect of non-repeating background images can be achieved.

For example, the following CSS style can set the background image of a div element to "myimage.jpg" and not display it repeatedly:

div {
background-image: url( myimage.jpg);
background-repeat: no-repeat;
}

2. Use the onerror attribute of the HTML img tag

In HTML, we can use the img tag to display image. Sometimes, we may encounter a situation where the image does not exist or cannot be loaded. At this time, we can use the onerror attribute to set an alternate image address to ensure that the page images are not repeated.

For example, the following img tag can point the incorrect "image.jpg" to the backup image "backup.jpg":

3. Use JavaScript to implement

If we need more complex logic in the future, HTML and CSS will not be able to meet our needs. At this time, we can use JavaScript to dynamically load and display images to achieve more flexible non-repeated display.

For example, the following JavaScript code first creates an array containing all the image addresses that need to be displayed. It then loops through the array, selecting an image address each time, and compares it with the array of image addresses already displayed to ensure there are no duplicates. Finally, the selected image address is added to the displayed image array, and the image is loaded and displayed.

var imgArray = ['image1.jpg', 'image2.jpg', 'image3.jpg', 'image4.jpg', 'image5.jpg'];
var displayedImgs = [];

function displayImgRandomly() {
do {

var imgIndex = Math.floor(Math.random() * imgArray.length);
var imgSrc = imgArray[imgIndex];

} while (displayedImgs.indexOf(imgSrc) !== -1);

displayedImgs.push(imgSrc );
var imgElement = document.createElement('img');
imgElement.src = imgSrc;
document.body.appendChild(imgElement);
}

The above three Both methods are simple and effective ways to achieve non-repeated display of images. The specific implementation depends on our needs and actual situation. By using basic HTML and CSS attributes, the onerror attribute of the img tag, and the flexible functionality of JavaScript, we can achieve efficient and beautiful non-repeating image display effects, thereby adding visual appeal and interest to web design.

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