Basic application methods of javascript embedded and external links

Basic application of javascript embedded and external links
Three ways to write JavaScript: inline, embedded, and externally linked

1. Inline
2. Embedded
3. External link

Basic application of javascript embedded and external links

The js language can be completely placed in the html language

But depending on the situation, it can be divided into embedded and external links.

When there is less js code, you can directly use the embedded method to introduce javascript through the <script></script> tag and related attributes

<!DOCTYPE html>
<html>
<script>
document.write("<h1>This is a heading</h1>");
document.write("<p>This is a paragraph.</p>");
</script>
<body>
 
</body>
</html>

However, in large projects and when there are a lot of javascript codes, you need to use external links.

When using external links, you need to create a new .js file first

<!DOCTYPE html>
<html>
<script type="text/javascript" src="1245.js">
</script>
<body>
 
</body>
</html>

Put the javascript code you need to write in the 1245.js file

Three ways to write JavaScript: inline, embedded, and externally linked

1. Inline

In the attributes of the HTML tag, the execution is triggered by the behavior. (Rarely used)

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2. Embedded

Wrap it in the HTML file using a script tag and it will execute automatically when the page is opened. (It’s easy to use, but don’t use it with large amounts of JS code.)

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3. External link

Written in a separate js file, introduced in the html file using the src attribute of the script tag, it will be automatically executed when the page is opened. (Recommended because there are various optimization methods)

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Note : It is rarely used in the industry, almost never used. Inline and external links cannot share the same script tag. In principle, the script tag of the external link can be placed anywhere. The script attribute of the external link is src , not href, not href, not href...

The above is my personal experience. I hope it can give you a reference. I also hope that you will support 123WORDPRESS.COM.

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