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What attribute does HTML introduce external javascript?

青灯夜游

Jun 30, 2021 pm 06:25 PM

htmljavascript

HTML introduces external javascript through the src attribute of the script tag, which specifies the URL of the external script file; the syntax is "

What attribute does HTML introduce external javascript?

The operating environment of this tutorial: windows7 system, HTML5&&javascript version 1.8.5, Dell G3 computer.

HTML introduces external javascript through the src attribute of the script tag.

The script element can either contain script statements or point to an external script file through the src attribute.

Sometimes, we need to run JavaScript in multiple pages of the website. Instead of writing the same script over and over, just create the JavaScript in a separate file, save it with a .js suffix, and reference that file using the src attribute in the <script> tag. </script>

Syntax

<script type="text/javascript" src="value"></script>

Value	Description
URL	The URL of the external script. Possible values are: Absolute URL - pointing to other sites (such as src="www.example.com/example.js") Relative URLs - pointing to files within the site (For example, src="/scripts/example.js")

Value

Description

URL

The URL of the external script. Possible values are:

Absolute URL - pointing to other sites (such as src="www.example.com/example.js")
Relative URLs - pointing to files within the site (For example, src="/scripts/example.js")

##Example:

<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
</head>
<body>
<script type="text/javascript" src="demo.js" ></script>
</body>
</html>

Output:

What attribute does HTML introduce external javascript?

Note:

Once the <script> tag uses the src attribute, it is used as a reference to an external file rather than inside the editing page. elements of the script. In other words, using src indicates that the element is suitable for referencing an external Javascript file and is not intended to insert a Javascript script into the page. <p>This shows that it should not and is not necessary (and useless) to insert code in the <script> tag that uses the src attribute. This can cause unpredictable results and, at least in most browsers, has no practical effect. If you add the following code to the example in this article: <p><pre class='brush:php;toolbar:false;'><script src="demo_script_src.js"> document.write("这个输出的内容来自本文件的 Javascript。"); </script></pre> It may parse the Javascript file referenced by the src attribute normally, but it may not execute any code edited directly within the <script> tag. Obviously, the many special properties of <script> (for example, some of its attributes can only be used for external files) determine that it is impossible to normally execute the referenced external file while taking into account the directly edited content in it. <p>[Related recommendations: <p>javascript learning tutorial<a href="https://www.php.cn/course/list/17.html" target="_blank">]<strong></script>

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