What is the difference between link tag and import?

The differences between link tags and import include syntax and usage, functions and features, loading timing, compatibility and support, etc. Detailed introduction: 1. Syntax and usage. The link tag is an HTML tag, used to introduce external resources into HTML documents, such as CSS style sheets, JavaScript scripts, icons, etc. import is the module import syntax in ES6, used in JavaScript files. Introduce external modules; 2. Functions and features. The link tag can introduce a variety of resources, such as CSS style sheets, icons, etc.

The operating system for this tutorial: Windows 10 system, DELL G3 computer.

In Web development, the link tag and import are both tags used to introduce external resources, but there are some differences between them.

Syntax and usage: The

link tag is an HTML tag used to introduce external resources, such as CSS style sheets, JavaScript scripts, icons, etc., into HTML documents. It is usually located in the tag and uses the rel attribute to specify the type of resource, such as stylesheet, icon, etc.

import is the module import syntax in ES6, used to introduce external modules into JavaScript files. It is typically used to bring in other JavaScript files so that the imported module can be used in the current file.

Functions and features:

The link tag can introduce a variety of resources, such as CSS style sheets, icons, preloaded resources, etc. It supports asynchronous loading and media queries, and can load different style sheets based on different devices or screen sizes. In addition, the link tag also supports page pre-rendering and pre-loading to improve page performance.

The import statement is used to import JavaScript modules, which can introduce variables, functions, classes, etc. exported from other JavaScript files. It supports modular development and can split the code into multiple modules to improve the maintainability and reusability of the code. In addition, the import statement also supports dynamic import, which can dynamically load modules based on conditions or events at runtime.

Loading timing:

The link tag loads external resources immediately during the HTML parsing process, and blocks the rendering of the page and the execution of the script until the resource loading is completed. This means that the browser will load the resources in the order of the link tags and wait for the resources to be loaded before continuing to parse and render the page.

The import statement only loads external modules during the JavaScript code execution phase, and it is dynamically loaded at runtime. This means that the import statement will not block the rendering of the page and the execution of the script, but will only load the imported module when it is needed. In addition, the import statement automatically handles dependencies between modules to ensure that modules are loaded in the correct order.

Compatibility and support: The

link tag is part of the HTML standard and is supported by almost all modern browsers. It is one of the main ways to introduce external resources in web development.

The import statement is a new feature of ES6 and needs to be used in browsers that support ES6 modules. Currently, most mainstream browsers already support the import statement, but it may not be fully supported in some lower version browsers. To ensure compatibility, you can use tools such as Babel to convert ES6 import statements into other supported modular syntaxes.

In summary, there are some differences between the link tag and import in terms of syntax, purpose, function and loading timing. The link tag is an HTML tag used to introduce external resources, while the import statement is the ES6 module import syntax used to introduce JavaScript modules. They are suitable for different scenarios and have differences in browser compatibility and functional features.

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