2019/6/3 to learn jQuery, previous studies have forgotten, now picked up again and decided to learn while recording
jQuery is a JavaScript library.
jQuery greatly simplifies JavaScript programming.
jQuery is easy to learn.
Directly in the official website to download the jQuery library jQuery
jquery-1.12.4.min.js: compressed version, suitable for production environments because the file is relatively small, in addition to comments, line feeds, spaces and other things, but basically no teeth readability.
jquery-1.12.4.js: uncompressed version, suitable for learning and development environment, source code clear and easy to read.
Version 1.x: IE678 compatible browser 2.x version: IE678 browser is not compatible with 1.x and 2.x versions jquery no longer updated version, now only updates 3.x version. 3.x versions: incompatible IE678, more streamlined (unpopular in the country, because the main purpose of the domestic use of jQuery is compatible IE678)
JQuery using three steps of:
1. jQuery introduced document 2. entry function 3. Function implemented
About jQuery entry function:
// first writing
$ (Document) .ready (function () {
});
// second writing
$ (function () {
});
Comparative jQuery entry function with entry function js
1. JavaScript function until the entry page for all resources (including images, file) loaded before you begin. 2. jQuery entry function will wait for finished loading the document tree began to perform, and not wait for the picture to load the file.