6 JavaScript

什么是 HTML JavaScript，为什么需要它？

With the help of code scripts, no one should be surprised at the possibilities of creating dynamic web pages。It is primarily used to build and implement applications on the client side with HTML5 or CSS3 markup。In other words, HTML JavaScript adds interactive components and aspects to keep visitors' attention, while HTML and CSS provide web page structure and design。

HTML 与 JavaScript 与 CSS

这是网站设计的三个最重要的工具。它们是我们在网络上看到的一切的基础。没有这三种语言的网站是不完整的，无法正常运行。

• HTML (Hypertext Markup Language) contains tags that define the structure and presentation of a document, such as headings, paragraphs, lists, links, and other semantic elements。
• JavaScript is used to develop interactive features like animation or to add interactivity to your site, such as form validation or search engine optimization。
• Finally, CSS is responsible for styling your website using colors and fonts to make it look attractive and professional。

The main purpose of hypertext is to define how text and graphics appear on web pages so that both robots and humans can read them。JavaScript, in turn, allows users to customize their web pages or control how they behave。它用于创建交互式、用户友好的网站。正因为如此，没有人谈论 JavaScript 与HTML 与 CSS的比较，因为今天，它们离不开彼此。

For comparison only: The HTML + CSS combination helps format, design, and position content on a web page。 The HTML + JS hybrid is a subset of hypertext that focuses primarily on creating interactive interfaces, animations, and user interaction for mobile or Web applications。

Without JS, developers design pages directly in HTML code, using tags and attributes to change fonts, colors, etc., which is a headache。那时唯一的希望是使页面具有交互性的 Flash。

JavaScript 是如何工作的

与大多数服务器端编程语言不同，JS 更偏向于客户端。它由用户浏览器的解释器在客户端处理。Client-side means that it is not executed on the server side (like PHP), but on the browser side。This is a huge advantage of scripting because any modern browser has a JS interpreter, so you only need one browser to use it。

Due to the full integration of JavaScript with hypertext markup, you can use it in HTML documents (or .php file, if it is responsible for markup) contains its code wherever appropriate。

HTML JavaScript 功能

• 更改元素样式并添加和删除标签。
• Execute the request to the server and download the data without reloading the page ( AJAX )
• Respond to events (scripts wait for certain events to occur, such as the end of page loading, mouse clicks, etc.)
• 显示消息、设置和读取 cookie。
• …以及更多。

HTML JavaScript 特性

这种语言的流行可以归因于以下特点：

• Responsive Layout - Your Bootstrap-based website can go from desktop to mobile in an instant。
• 作品集 - 以美观的方式轻松展示您的作品。
• jQuery - Make your website stand out with a unique and visually stunning design。
• 延迟加载 - 不需要在您的网站上加载大量时间的效果。
• Static - Clean interface, minimal code, make web pages faster without worrying about wasting bandwidth。
• Retina Ready - designed for high resolution, so your content looks sharp。
• 视差 - 您的图像具有深度效果，不仅在前面而且在后面。
• 24/7 支持- 如果您有任何问题，我们会提供全天候免费帮助。

HTML JavaScript 的高效用例

如前所述，在前端工作需要JS。More specifically, JS is used to control browser Windows, change document content when accessing the DOM, and handle various operations on web pages。Typical examples of JS you can see on a daily basis are pop-up messages, navigation bars, IFrames, weather forecasts, and other dynamic elements。Although the language has many possibilities, it is mainly used to make the user experience more interesting。

You can use HTML JavaScript for many purposes, such as:

• 创建交互式网站；
• 在图表、图形或地图中显示动态数据；
• 向网站添加动画；
• 创建游戏；
• 建筑应用。

In other words, JS can be used freely on different platforms, including Web, mobile applications, desktop web applications, and embedded applications。

在网站上使用互动功能

用户可以与网站互动。Here are just a few ways JS can be used on web pages;There are no restrictions on what you can do with it:

• 更改图像比例（放大/缩小）。
• 音频和视频播放。
• 按下按钮可打开或隐藏其他数据/详细信息。
• 显示动画图形。
• 当光标在元素上时更改元素的颜色。
• 滚动图片轮播。
• 显示倒计时或计时器。
• 下拉、折叠菜单的实现。

开发移动和基于 Web 的应用程序

HTML JavaScript helps create interactive interfaces, animations, and user interaction for mobile and Web applications。

移动应用程序。它是用于构建移动应用程序的最流行的代码语言之一。Many companies, such as Netflix, Microsoft, Amazon, and Google, use it to develop their applications。例如，JS 比 Java 或 Python 更容易学习。It also makes it easier for developers to create complex web pages with rich user interfaces that run smoothly on any device, including smartphones and tablets。

网络应用程序。 HTML JavaScript is also used in Web development, where it helps developers make web-based software with faster load times, better interaction, and easier to use user interfaces。基于 Web 的应用程序的一些实例是：

• Services that allow you to book accommodation, tickets and tables on the Internet。
• 在线交易方式。
• 需要用户输入的站点，例如注册数据。
• 用于多任务处理和处理大量数据的 CRM 程序。

如何将 JavaScript 添加到 HTML 文件

So here's how to use JavaScript in HTML5。To integrate code into a document, you need to wrap the main code with a script tag, as this example shows:

<脚本>

document.getElementById("demo").innerHTML = 15.50;

script 标签通常出现在 body 元素的底部。You can also use JavaScript on any element in the body, such as an input field or button。此外，您可以像本例中那样插入 .js 文件：

哪种类型的 JS 框架最适合您的网站？

There is no one-size-fits-all framework, as each site has unique needs。 The choice of HTML JavaScript framework depends on the size and complexity of your site and how much time you want to spend building it。Also, it depends on how long it takes, what budget do you have, what skills do you have, etc.。

什么是 jQuery 以及它在哪里使用

jQuery is a library based on the HTML JavaScript programming language that is used by almost every website today。这个库简化了许多不想深入 JS 的开发人员的生活。

JQuery is a framework that contains many tools for working with Web documents。It allows you to solve typical tasks more quickly, such as form validation, slider creation, and so on。使用纯脚本，问题会更难解决。

jQuery 设计具有许多需要使用的特性：

• CSS样式表规则；
• 事件处理；
• 动画和各种效果；
• 在 DOM 中显示对象；
• AJAX技术。

To connect to the jQuery library, you first need to upload a file or establish a remote connection via a CDN (the file is loaded with the page)。您可以按如下方式连接已上传的代码：

As such, jQuery is a high-quality JavaScript simplification, especially for those who don't want to put up with it for long。 jQuery is accessible and cross-browser, which is very important when you work。

什么是反应 JS？

React is a JS library designed to simplify the management of interfaces in Web applications。 React 的一个显着特点是您可以使用它来创建托管UI 组件These components help you easily scale your project to large Web applications。

React is based on the concept of virtual DOM, which is a mirror image of the real DOM。 React starts to catch changes and update the real DOM as they happen。 The Virtual DOM concept speeds up application processing and improves performance。Virtual DOM nodes act as containers for the real DOM elements they represent and are rendered according to the current state of the application。例如，在查看时，输入字段将反映对其值所做的任何更改。此外，React 的数据结构支持高效更新和后续渲染。This makes it possible to update components immediately after adding or removing items in their structure without re-rendering。As a result, React is faster than all legacy JS-based frameworks and libraries。

AngularJS 框架怎么样？

Angular's main advantage is its clean structure, which makes it ideal for large projects and for loading Web applications with complex business logic。与其他框架相比，它配备了更多的默认工具和定制解决方案。You will also receive a set of guidelines, scripts, and syntax that you must follow for connections and widgets to function properly。 Angular is popular among developers who need to manage multiple teams。It is tightly structured internally, optimizing teamwork but not limiting the implementation of the most unusual features。

VueJS：它是什么？

Vue JS is an HTML JavaScript library for building user interfaces。因此，可以快速开发 UI，无论它们是基本的还是复杂的。多年来，Vue.js has grown significantly, with new features and third-party packages regularly released into the core library。事实上，它最近因其简单性和灵活性而受到欢迎。The framework has a small learning curve and is easy to use with front-end libraries like React or Angular。

什么是 EmberJS？

Ember JS is a library that helps developers create complex Web applications。这也有助于他们管理应用程序的数据和交互。 EmberJS has been used by companies such as Lyft, Yahoo, and Netflix, who see its benefits in their product development process。 Ember JS is an open source project, which means anyone can contribute to or build it。The project was born in 2011 and has become one of the most popular frameworks for building Web applications on the market today。

如何选择具有正确特性和优势的 JS 框架

The framework you choose should be "future-proof" so that you don't have to worry about any major changes in the future。大多数框架都有很多特性，因此很难知道哪个框架值得投资。这里有一些关于如何选择 JS 框架的提示：

1. 知道你想从中得到什么：你的目标是什么？你想要原型制作的东西吗？还是您需要一些供企业级使用的东西？
2. 了解框架提供什么：它是否提供模块化？是否支持不同的编程语言或技术？
3. Consider what other developers think: See reviews, blogs, and articles written by other developers who have used that or the framework。
4. 做出明智的决定：不要只购买任何 JS 框架。做你的研究，找到一个完全符合你需要的！

Basic steps for building an effective e-commerce website using HTML JavaScript

这是一份实用指南，可帮助您启动电子商务网站项目。It covers the basic steps you should consider when building your website and will help you avoid costly common mistakes。

网站目的

Your e-commerce site is always evolving, so it's vital to be able to adapt and change according to the changing needs of your customer base。You will find many ways to use a website for different purposes, but there is one main reason why people decide to set up an e-commerce website。That's because they're passionate about the product they're selling, or it's a fun hobby they love and want to share with as many people as possible。那你的目的呢？

预算

It is important to consider how much budget you want to allocate to your HTML JavaScript project。您应该确保不要忘记构建网站所带来的托管、软件和其他费用。许多人可以免费开发他们的网站，但并不是每个人都这样。These scripts range in price from $10 to $40, so the purchase will not affect the developer's finances。

竞赛

Understanding how you will compete with other similar markets to build a successful website that attracts your customers and keeps them coming back time and time again is critical。The most critical thing you can do to make your business successful is to study the competition。

• 他们的网站是什么样的？
• 他们多久更新一次内容？
• 他们使用什么关键字/短语进行搜索？
• 是什么让他们在客户面前脱颖而出？

市场调研过程

任何商业计划的第一步都是市场调查。It's the process of understanding your customers, their needs, how they use technology and where your competitors fit into it。

研究您的市场：

• 他们主要关心什么？
• 他们的购买习惯是什么？

创建您的想法或概念：

• 你会提供什么，你为什么要提供它？
• 谁将是您的目标客户？
• 他们希望在您的网站上看到哪些产品/服务？

网站生态系统工具

The tools you will use throughout the website design process will vary, depending on the tools and technology stack your team has developed over time。但是，一些基本选项包括：

• Photoshop or Adobe Creative Cloud;
• Sketch App 或 InVision；
• 线框图；
• And other software for graphic design, photo and video editing, Web development, high-fidelity model creation, and wireframing tools for prototyping。

网站设计

您应该考虑网站的设计类型。需要考虑的一些事情是：

• 配色方案。
• 您希望网站上具有的功能。
• 您正在计划多个页面。

选择 HTML5 模板

您可以使用两个选项：

• You can choose to use free website themes and customize them according to your personal needs。
• 或者您可以购买高级HTML5 模板，它可用于商业和个人用途。

如何选择 HTML JavaScript 插件

为您的网站选择合适的插件是至关重要的一步。This will help you find the right balance between what you want and what your website can support。To help you decide which are the best plugins, we have compiled a list of these plugins that you can download from Templateog体育首页。

• 来自 Zemez 的响应式导航栏。用于创建响应式菜单的多功能导航栏脚本。该插件流畅地呈现导航栏，以适应屏幕的大小。它还可以确保您的网站在移动设备上看起来不错。
• 音频转换器。 PHP scripts convert audio files to other formats such as MP3, AAC, WAV, WMA, OGG, etc。它具有易于使用的界面并支持所有音频类型。
• 图像悬停效果。该脚本将常规图像转换为动画图像效果。It has an intuitive, easy-to-use interface, supports multiple browsers, and complies with web standards。将它集成到任何站点都非常简单。The script can be run with or without Angular, Vue, React, and other frameworks。
• 定制衬衫设计师。用于生成自定义服装设计的 jQuery 插件。The plugin allows you to customize shirts, blouses, jackets, and more by selecting fabrics, accessories, and dimensional parts。
• 来自 Novi 的页面生成器。The Visual Content Editor helps you import HTML templates, build web pages visually, and easily edit content on web pages without coding。