Detailed explanation of how to introduce jQuery core files
jQuery is a popular JavaScript library that simplifies many operations in web development. Before using jQuery, you must first understand how to introduce the jQuery core file. This article will discuss in detail how to introduce jQuery core files, and attach specific code examples.
1. CDN introduces jQuery
A common way is to introduce jQuery core files through CDN (Content Delivery Network). This method is not only fast, but also convenient and fast. The following is the CDN link that introduces jQuery:
<script src="https://cdn.jsdelivr.net/npm/jquery@3.5.1/dist/jquery.min.js"></script>
Add the above code in the HTML file to introduce the latest version of the jQuery core file. Please note that the version number in this link may be updated over time, so make sure you are pulling in the latest version.
2. Importing jQuery from local files
In addition to importing through CDN, we can also download the jQuery core file to the local and import it through a relative or absolute path. First, we need to download the jQuery file first. You can download the latest version from [official website](https://jquery.com/download/).
Assuming that we save the jQuery file to the js folder of the project, we can use the following code to import it:
<script src="js/jquery-3.5.1.min.js"></script>
In this way, the local jQuery core file can be imported.
3. Use NPM to install and introduce jQuery
If the project uses Node.js and the npm package manager, you can use the npm command to install jQuery and introduce it through the import or require statement.
First, execute the following command in the project root directory to install jQuery:
npm install jquery
Then, use the following method to introduce jQuery in the JavaScript file:
import $ from 'jquery';
Or use the require method:
const $ = require('jquery');
Through the above method, we can introduce the jQuery core file into the project.
4. jQuery core file introduction order
In actual projects, in order to ensure that jQuery can run correctly, it is usually necessary to ensure that the jQuery core file is introduced before other JavaScript files. This is because many jQuery plugins and code rely on the functionality of the jQuery core library.
<script src="js/jquery-3.5.1.min.js"></script>
Conclusion
This article details several ways to introduce jQuery core files, including through CDN, local files and npm installation. No matter which method is used, you need to ensure that the jQuery core file is introduced before other scripts to ensure the normal operation of the project. I hope this article can help readers better understand how jQuery is introduced.
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