


What is the difference between jquery and document for getting html elements?
Difference: The html element obtained by jquery is a jquery object and can execute jquery methods, while the document obtains a dom object and executes dom methods. jQuery objects are unique to jQuery and cannot use DOM methods; and DOM objects cannot use jQuery methods.
Related recommendations: "jQuery Tutorial"
Recently made a video plug-in through ocx, and then put the plug-in Go to html (if you want to know, you can take a look)
Because I want to operate this plug-in, play, stop, etc., so I need to get this element. As expected, I use jquery to get it, and then It cannot be executed at all, and then use document to obtain it and execute it normally. The details are as follows
//正常执行 var obj = document.getElementById("player00"); obj.testhelloworld();//无法执行var playobj = $('#player00'); playobj.testhelloworld();
Then I was thinking,What is the difference between the two? Then I searched for the following conclusions
The html element obtained by jquery is a jquery object and can execute jquery methods, while the document obtains a dom object and executes dom Method
Description:
DOM object is an object we obtain using traditional methods (javascript), and jQuery object is an object obtained using jQuery’s class library selector . A JQuery object is an object generated by wrapping a DOM object with jQuery. The JQuery object is unique to jQuery. It can use methods in jQuery, but cannot use DOM methods.
I was relieved. I had always thought that the two were equivalent, and I wanted to find out why dom Why can't the method be executed in jquery? Now that I think about it, I feel completely relieved.
In this case, how do transform the two into each other? After all, the contents of the obtained objects are the same.
Convert jQuery object to DOM object:
Two conversion methods convert a jQuery object into DOM object: [index] and .get(index);
(1) The jQuery object is a data object, and the corresponding DOM object can be obtained through the [index] method.
For example:
var $v =$("#v") ; //jQuery对象 var v=$v[0]; //DOM对象 alert(v.checked) //检测这个checkbox是否被选中
(2) jQuery itself provides, through the .get(index) method, the corresponding DOM object is obtained
For example:
var $v=$("#v"); //jQuery对象 var v=$v.get(0); //DOM对象 alert(v.checked) //检测这个checkbox是否被选中
Convert DOM object to jQuery object:
For a DOM object that is already a DOM object, you only need to wrap the DOM object with $() to get a jQuery object. $(DOM object)
For example:
var v=document.getElementById("v"); //DOM对象 var $v=$(v); //jQuery对象
After conversion, you can use any jQuery method.
Through the above methods, jQuery objects and DOM objects can be converted to each other at will. What needs to be emphasized again is that only DOM objects can use methods in DOM, and jQuery objects cannot use methods in DOM.
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