jquery objects and JavaScript objects that are DOM objects are converted to each other

jquery objects and JavaScript objects that are DOM objects are converted to each other

1. DOM object into JQuery object
For a DOM object, you just need to wrap the DOM object with $ () and you can get a JQuery object, $ (DOM object) Note: VAR is a variable defined
Such as:

var v = document.getElementById ("V"); /dom object
var $v = $ (v);//jquery Object
After conversion, you can use JQuery in any way.
2. JQuery objects into DOM objects
Two ways to convert a jQuery Objects into DOM objects: [index] and. get (index);
(1) The JQuery object is a data object that can be used by the [index] method, To get the corresponding DOM object.

var $v = $ ("#v");//jquery Object
var v = $v [0] ; DOM object
alert ( v.checked); Detects whether the checkbox is selected
(2) The jQuery itself is provided by the. Get (index) method to get the corresponding DOM object
example:

var $v = $ ("#v"); JQuery Object
var v = $v. Get (0); Dom Object ($v. get () [0] can also)
alert (v.checked); Detects if the checkbox is selected

jquery objects and JavaScript objects that are DOM objects are converted to each other