Where is javascript generally placed?

Where is JavaScript generally placed on web pages?

As an important part of modern web development, JavaScript can make web pages more dynamic. I believe many people have used JavaScript in the process. However, a problem that always troubles many beginners is where JavaScript should be placed on the web page. This article will help readers understand how to choose the appropriate placement location based on common scenarios in current web development.

1. Put it in the tag
   In the head of HTML, that is, in the tag, JavaScript can be placed in the <script> tag. This method is usually used for operations that include referencing external JavaScript libraries. JavaScript scripts can be defined uniformly at the head of the web page so that corresponding processing can be achieved by calling the library elsewhere on the web page, for example: </script>

< ;head>

<title>xxx</title>
<script src="jquery.js"></script>
<script type="text/javascript">
    // 自定义JavaScript代码
</script>

You can see that by referencing external library files in the

tag, such as the jquery.js above, you can use A piece of custom JavaScript code calls the API interfaces of these libraries for data processing. The advantage of this is that you can easily maintain different JavaScript library files. At the same time, you can also fully consider the search engine inclusion rules when doing SEO optimization to ensure that search engines will not have problems with the inclusion of web pages.

2. Put it in the tag
   In addition to placing JavaScript code in the tag, you can also place the code anywhere in the tag. This method can ensure that the latest effects of the JavaScript code are displayed immediately when the web page is displayed, allowing various elements on the web page to achieve more interactive effects, such as:

gt ;

<title>xxx</title>

<button onclick="alert('Hello World')">按一下试试</button>
<script type="text/javascript">
    // 自定义JavaScript代码
</script>

< ;/html>

As you can see, the advantage of this is that it can make the code more convenient to interact with each other, which is called truly "enhanced reading experience". Of course, this method is also prone to a shortcoming, especially when there are many JavaScript codes in the web page that need to be loaded, it may occupy too much bandwidth resources of the web page, causing the website to display too slowly.

In summary, JavaScript code can be placed in the

or tag of the web page, depending on the actual application scenario. Generally speaking, placing small JavaScript code snippets within HTML sub-elements can easily make web pages more interactive, while referencing code from external JavaScript libraries in the tag can facilitate the maintenance and management of custom JavaScript code. Of course, you also need to pay attention to the overall performance of the web page. Using asynchronous loading during complex Javascript operations can avoid the problem of long web page rendering time. I hope this article can solve this confusion for readers and make JavaScript code more effective and practical!

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