JS Common Execution method

$ (document). Load ();

This method is executed when the Web page and its accompanying resource files, such as css,scripts, pictures, etc., are loaded.
Often used to detect whether the page (and its accompanying resources) is loaded.


$ (document). Ready ();
This method is triggered when the page DOM object is loaded and the Web browser is able to run JS. If you want to execute JS as soon as possible, you can use this method. [In the Script tab of the HTML header, the JS code that is not in ready () will be executed earlier than the Ready ()]


$ (document). Unload ();
This event is triggered when the page is stopped, which may exist in the refresh Operation/f5, click the previous Page button, go to another page, or close the entire tab or window.

All in all, their order of invocation is ready () >> load () >> unload ().