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所在平台: Udemy |
课程主页: https://www.udemy.com/course/dynamic-html/
课程评论：没有评论
**课程名称：** 动态 HTML：HTML、JavaScript 和 CSS 的结合 **课程概述：** 本课程介绍动态 HTML（DHTML），这是一个综合性的术语，涵盖了一系列用于创建交互式和动画网站的技术。DHTML 的核心在于将静态标记语言（如 HTML）、客户端脚本语言（如 JavaScript）以及表示定义语言（如 CSS）结合起来，并利用文档对象模型（DOM）。 通过 DHTML，脚本语言可以修改网页的定义语言中的变量，从而在页面加载完成后甚至在用户浏览过程中，改变原本“静态”的 HTML 内容的外观和功能。因此，DHTML 的动态性体现在页面浏览过程中的交互和变化，而非每次页面加载时生成独一无二的内容。 与一般的“动态网页”概念不同，后者涵盖了根据用户、加载或变量值生成不同页面的所有情况（包括客户端脚本和服务器端脚本如 PHP、Python、JSP 或 ASP.NET）。DHTML 则侧重于在客户端实现的动态效果，其页面加载仍基于请求/重新加载。DHTML 页面加载后，客户端与服务器之间的交互可能并不存在，所有处理都在客户端的 JavaScript 中完成。 **DHTML 与 AJAX 的区别：** DHTML 的一个关键区别在于其“请求/重新加载”的基础。虽然 DHTML 可以使用 DHTML 的特性发起与服务器的请求（或“子请求”）来执行其他操作，但其本质上是独立的。例如，一个具有多个标签页的页面，纯 DHTML 方法会加载所有标签页的内容，然后仅动态显示活动标签页。而 AJAX 可以按需加载每个标签页的内容。 **DHTML 的主要优势和应用：** DHTML 允许作者通过修改 DOM 和页面样式，实现其他技术难以达到的页面效果。HTML、CSS 和 JavaScript 的结合为以下功能提供了途径： * **动画效果：** 为文档中的文本和图像添加动画。 * **动态内容展示：** 嵌入股票行情、最新新闻等自动刷新内容的“跑马灯”或其他动态显示。 * **客户端交互：** 使用表单捕获用户输入，并在不重新发送数据到服务器的情况下进行处理、验证和响应。 * **交互式用户界面：** 实现翻转按钮或下拉菜单等交互元素。
Dynamic HTML, or DHTML, is an umbrella term for a collection of technologies used together to create interactive and animated websites by using a combination of a static markup language (such as HTML), a client-side scripting language (such as JavaScript), a presentation definition language (such as CSS), and the Document Object Model.DHTML allows scripting languages to change variables in a web page's definition language, which in turn affects the look and function of otherwise "static" HTML page content, after the page has been fully loaded and during the viewing process. Thus the dynamic characteristic of DHTML is the way it functions while a page is viewed, not in its ability to generate a unique page with each page load.By contrast, a dynamic web page is a broader concept, covering any web page generated differently for each user, load occurrence, or specific variable values. This includes pages created by client-side scripting, and ones created by server-side scripting (such as PHP, Python, JSP or ASP.NET) where the web server generates content before sending it to the client.DHTML is differentiated from Ajax by the fact that a DHTML page is still request/reload-based. With DHTML, there may not be any interaction between the client and server after the page is loaded; all processing happens in JavaScript on the client side. By contrast, an Ajax page uses features of DHTML to initiate a request (or 'subrequest') to the server to perform additional actions. For example, if there are multiple tabs on a page, pure DHTML approach would load the contents of all tabs and then dynamically display only the one that is active, while AJAX could load each tab only when it is really needed.DHTML allows authors to add effects to their pages that are otherwise difficult to achieve, by changing the Document Object Model (DOM) and page style. The combination of HTML, CSS and JavaScript offers ways to:Animate text and images in their document.Embed a ticker or other dynamic display that automatically refreshes its content with the latest news, stock quotes, or other data.Use a form to capture user input, and then process, verify and respond to that data without having to send data back to the server.Include rollover buttons or drop-down menus.
