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What are the differences between js css

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Apr 24, 2023 am 09:08 AM

JavaScript (JS for short) and Cascading Style Sheets (CSS for short) are the two most commonly used programming languages in web development. Although they are both used for the presentation and interaction of web pages, their purposes are very different. This article will introduce the difference between JS and CSS.

JavaScript is a scripting language, CSS is a style language

JavaScript is an object-oriented, prototype-based scripting language that allows programmers to Code to achieve dynamic effects and interactions on web pages. It allows you to interact with the DOM (Document Object Model) to change the content, structure, and style of the page.

CSS is a style sheet language used to define the appearance and layout of web pages. It can define the color, font size, background color and other attributes of elements through style rules. CSS has no direct relationship with the content of the web page. It is only responsible for defining the style of the web page.

JavaScript is used for dynamic interaction and manipulation, CSS is used for fixed styles and layouts

JavaScript allows you to use control structures such as loops, conditional statements, and event handlers to control Web pages perform dynamic operations. It can be executed immediately when the page loads, or in response to an event being fired.

CSS is used for layout and styling and can usually only be loaded once when the page loads. It cannot respond to events or change the structure of the web page. However, it can use advanced features of media queries and style sheets to manage web page styles.

JavaScript can change the content and structure of web pages, CSS is only responsible for style

JavaScript can dynamically change the content and structure of web pages. For example, you can use JavaScript to change the properties of a web page element or create a new element when a button or link is clicked.

CSS cannot change the content or structure of the document. It can only control the style of the element. However, it is possible to control the styling of specific elements using attribute selectors and pseudo-elements.

JavaScript can handle complex logic, CSS is only used for styling

JavaScript can use conditional and loop operators to handle variables, functions and objects. It can implement complex logic processing, such as form validation, calculation and animation effects, etc.

CSS focuses on style and cannot handle the complex logic of JavaScript. It can be styled using simple selectors and properties.

JavaScript can communicate with the server side, CSS does not have this ability

JavaScript can communicate with the server side through AJAX technology, obtain data and update web page content. It can send GET and POST requests, and handle responses.

CSS does not have the ability to communicate with the server side. It can only be used for styling and layout.

Summary: JavaScript and CSS have their own characteristics and uses. JavaScript is used for dynamic effects and interactivity, and can handle the complex logic of web pages and communicate with the server side. CSS is used to define the style and layout of web pages. It is only responsible for presentation and style control and does not handle logic and interaction. For web developers, it is extremely important to have good coordination between the two programming languages when implementing web pages.

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