js remove css

JavaScript is a powerful programming language used for developing interactive web applications. In web development, it is widely used to develop dynamic pages and client-side scripts. An important feature of the JavaScript language is the ability to manipulate the Document Object Model (DOM). We can use JavaScript to manipulate the DOM, including creating, modifying, and deleting elements. This article will explore how to remove CSS using JavaScript.

CSS (Cascading Style Sheets) is a language used to describe the appearance and style of web page elements. The main function of CSS is to make website design more unified and professional. It does this by applying styles to HTML elements. Sometimes, we need to remove or change CSS at runtime to rearrange the page or change the style of elements. Fortunately, JavaScript provides several ways to accomplish this task.

1. Use the removeAttribute() method

The removeAttribute() method is used to remove the specified attribute from the element. This method can be used to remove the style attribute, which contains the element's CSS rules. To remove the style of an element, use this simple code:

document.getElementById('element-id').removeAttribute('style');

In this code, we use The getElementById() method gets the element with the specified id, and then uses the removeAttribute() method to delete its style attribute.

2. Use the className attribute

The className attribute contains the CSS class of the element, which can be used to dynamically change the style of the element. To remove the class of an element, use this simple code:

document.getElementById('element-id').className = '';

In this code, we use getElementById( ) method gets the element with the specified id and then sets its class name to an empty string. This will remove all class names from the element, including CSS styles.

3. Use the introduction and removal of external CSS

In addition to removing CSS from elements, we can also use the introduction and removal of external CSS files to dynamically change the overall style of the web page. Here is a simple code for bringing in an external CSS file in JavaScript:

var link = document.createElement('link');
link.rel = 'stylesheet';
link .type = 'text/css';
link.href = 'style.css';
document.getElementsByTagName('head')[0].appendChild(link);

This code , we use the createElement() method to create a element. We then set the attributes of this element, including rel, type, and href, which tell the browser where to find the external CSS file and how to use it. Finally, we use the getElementsByTagName() method to get the element and add the element at the end of it, thus introducing the external CSS file.

To remove external CSS files, use this simple code:

var links = document.getElementsByTagName('link');
for (var i = 0; i < links.length; i ) {
if (links[i].href.indexOf('style.css') != -1) {

links[i].parentNode.removeChild(links[i]);

}
}

In this code, we use the getElementsByTagName() method to obtain all elements and use a loop to traverse them. If the href attribute of the found element contains the specified CSS file name (in this case, style.css), we remove it from the document using the parentNode.removeChild() method.

Summary

In this article, we explored how to remove and change CSS using JavaScript. We used several methods, including the removeAttribute() method, the introduction and removal of the className attribute and external CSS. These techniques can dynamically change CSS at runtime, thereby rearranging the page or changing the style of elements. Mastering these techniques will make you more confident and effective in web development.

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