jquery Objects and Dom objects

1 What is jquery?

jquery is a package of JS, the underlying code is written in the JS code. It encapsulates a lot of methods and properties that we can use directly, without having to worry about how others are implemented, just by learning to call.

2 Why study jquery?

First, the native JS code has several disadvantages:

A: Compatibility issues

B: More repetitive code

C: Poor fault tolerance

The method name provided by D:dom is too long and easy to write wrong

The advantages of jquery:

A: Lightweight (file is small)

B: The DOM operation is encapsulated, simple to operate

C: Support chain-type operation

D: Support for rich plugins

E: Ajax Support

.....

jquery version?

There are currently 3 large versions of 1.x 2.x 3.x

Version 1.x supports IE6, 7, 8

2.x 3.x version does not support IE6, 7, 8

3: What is a jquery object and what is a DOM object?

jquery object: The element that is obtained through the jquery method is the jquery object

Dom object: The element obtained by the JS method is the DOM object

Note: jquery objects cannot use the properties and methods of Dom objects

DOM objects cannot use the properties and methods of jquery objects

4:jquery objects and DOM objects convert to each other?

A:dom object to jquery object?

var Odiv=document.getelementbyid (' Div1 ');

var jquery object =$ (Odiv);

B:jquery object to Dom object?

1:var odiv=$ (' div ') [0];

2:var odiv=$ (' div '). Get (0);

jquery Objects and Dom objects