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Home Web Front-end JS Tutorial Understand JavaScript basics (very detailed)

Understand JavaScript basics (very detailed)

Feb 24, 2021 am 10:23 AM

Understand JavaScript basics (very detailed)

Free learning recommendation: javascript video tutorial

##What isJavaScript

##JavaScript is a scripting language that is object- and event-driven and has security features. It has been widely used in Web application development. It is often used to add various dynamic functions to web pages and provide users with Smoother and more beautiful browsing effect. Usually JavaScript scripts realize their functions by embedding them in HTML. JavaScript

Features is an interpretive script Language (the code is not precompiled).

  1. is mainly used to add interactive behaviors to HTML (an application under Standard Universal Markup Language) pages.

  2. can be directly embedded in HTML pages, but writing it as a separate js file is beneficial to the separation of structure and behavior.

  3. Cross-platform features, with the support of most browsers, can run on multiple platforms (such as Windows, Linux, Mac, Android, iOS, etc.).

  4. JavaScript

Composed

Daily uses of JavaScript

Embed dynamic text into HTML pages.

  1. Respond to browser events.

  2. Read and write HTML elements.

  3. Validate data before it is submitted to the server.

  4. Detect the visitor’s browser information.

  5. Control cookies, including creation and modification.

  6. Server-side programming based on Node.js technology.

  7. The basic structure of JavaScript

<script type="text/javascript">
    <!—
          JavaScript 语句;
    —>
</script >
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Example:

……
<title>初学JavaScript</title>
</head>
<body>
<script type="text/javascript">
    document.write("初学JavaScript");
    document.write("<h1>Hello,JavaScript</h1>");
</script>
</body>
</html>
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<script>…</script> can be included anywhere in the document, as long as the code is used It has been read and loaded into memory before

JavaScript

Execution principle

## Method1.Use

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