JavaScript (20) add and delete elements in jQuery HTML

JQuery-add element
With jQuery, you can easily add new elements/content.

Four jQuery methods for adding new HTML content:

• Append ()-insert content at the end of the selected Element
• Prepend ()-insert content at the beginning of the selected Element
• After ()-insert content after the selected Element
• Before ()-insert content before the selected Element
  The jQuery append () method inserts content at the end of the selected element.
  

  $("p").append("Some appended text.");

  
  The jQuery prepend () method inserts content at the beginning of the selected element.
  

  $("p").prepend("Some prepended text.");

  
  The jQuery after () method inserts content after the selected element.
  

  $("img").after("Some text after");

  
  The jQuery before () method inserts content before the selected element.
  

  $("img").before("Some text before");

  
  What is the difference between the first two and the last two... I'm thinking about it... Code Analysis:
  

  <Script src = "jquery-1.11.1.js"> </script> <script> $ (document ). ready (function () {$ ("# btn1 "). click (function () {$ ("# test1 "). prepend ("Before") ;}); $ (" # Btn2 "). click (function () {$ (" # test1 "). append ("After") ;}); $ (" # Btn3 "). click (function () {$ (" # test2 "). before ("Before") ;}); $ (" # Btn4 "). click (function () {$ (" # test2 "). after ("After") ;}); </Script>Add text in front of Fan tesiAdd text after fan terseyAdd text before fan tersiAdd text after still fan tersi
  Versace
  Still ventsi

  It feels troublesome to map images... Or text description... After clicking the four buttons, the effect is as follows:
  

  BeforeVersaceAfter

  Before

  Still ventsi

  After
  
  Did you find something... Continue, review elements:
  
  Append () and prepend () methods, within the selected element (

  ............

  ) Insert content;
  After () and befZ finished? Http://www.bkjia.com/kf/ware/vc/ "target =" _ blank "class =" keylink "> memory + ceiling/SBqUXVlcnmjrL/J0tS63Mjd0te12Mm + s/ceiling + ceiling/ycq508PS1M/ceiling + PGJyPgo8dWw + ceiling s/second + CjxwcmUgY2xhc3M9 "brush: java; "> $ (" # div1 "). remove ();
  The jQuery empty () method deletes the child elements of the selected element.
  

  $("#div1").empty();

  
  Filter deleted elements
  The jQuery remove () method can also accept a parameter that allows filtering of deleted elements.
  This parameter can be the syntax of any jQuery selector.
  The following example deletes all

  Element:
  

  $("p").remove(".italic");

  Here I thought about how to "delete all class =" italic"

  Element and delete

  All class = "italic" elements "... That is:
  

  $(".italic").remove("p");

  Can the empty () method accept a parameter? The answer is no!
  
  
  Another problem is that the following code is displayed:
  

  Var txt2 = $ ("
  "). Text (" Text. "); // create a new element with jQuery

  Why can it be written in the above form? I am not quite clear about the rules... As you study in the future, you should know that day, haha... Put it here first ......