Preload js code of css or javascript_javascript tips

There are generally two common ways to preload files: xhr and dynamically inserting nodes. Dynamically inserting nodes is the simplest and most widespread asynchronous loading method (such as yui's Get module). Then files loaded using the dynamically inserted node method will be executed immediately after loading. On the one hand, the execution of javascript will occupy the browser's js execution. The process, on the other hand, may also change the page structure, and the execution of css is more likely to change the entire page. Although the xhr method will not execute scripts, due to the restrictions of the same domain, and the static files of the website are now deployed on the CDN server, how to preload css js files has become a bit mysterious.

Stoyan Stefanov concisely explains a way to load a file without letting it execute. The original text can be found at http://www.phpied.com/preload-cssjavascript-without-execution/

The specific method is to use new Image().src in IE to preload the file , while other browsers use dynamically inserted