The basic design idea and main usage of jquery

Select a page element, and then do something about it

$ (document)//Select Entire Documents Object

$ (' #myId ')//select page element with ID myId

$ (' div.myclass ')//select div element with class MyClass

$ (' input[name=first] ')//Select the name attribute equals first INPUT element

$ (' A:first ')//Select First a element in Web page

$ (' tr:odd ')//select odd rows of the table

$ (' #myForm: Input ')//Select INPUT element from form

$ (' div:visible ')//select the visible div element

$ (' Div:gt (2) ')//Select all DIV elements except the first three

$ (' div:animated ')//Select a DIV element that is currently in the animated state

$ (' div '). has (' P '); Select the div element that contains the P element

$ (' div '). Not ('. MyClass '); Select a DIV element that is not equal to the MyClass class

$ (' div '). Filter ('. MyClass '); Select a DIV element with class equal to MyClass

$ (' div '). First (); Select a 1th div element

$ (' div '). EQ (5); Select a 6th div element

$ (' div '). Next (' P '); Select the first P element after a DIV element

$ (' div '). parent (); Select the parent element of the DIV element

$ (' div '). Closest (' form '); Select the form parent element closest to Div

$ (' div '). Children (); Select all child elements of Div

$ (' div '). siblings (); Select sibling elements of Div

$ (' div '). Find (' H3 '). EQ (2). html (' Hello ');

$ (' div ')//Find DIV element

. Find (' H3 ')//Select one of the H3 elements

. EQ (2)//Select a 3rd h3 element

. html (' Hello '); Change its contents to Hello

$ (' H1 '). html (); HTML () has no parameters, which means that the value of H1 is removed

$ (' H1 '). html (' Hello '); HTML () has parameter Hello, which means to assign a value to the H1

. HTML () to remove or set HTML content

. Text () to remove or set text content

. attr () to remove or set the value of a property

. width () to remove or set the width of an element

. Height () to remove or set the height of an element

. Val () takes out the value of a FORM element

. InsertAfter () and. After (): Inserts an element from behind an existing element

. InsertBefore () and. Before (): Outside the existing element, insert the element from the front

. AppendTo () and. Append (): Inserts an element from behind within an existing element

. Prependto () and. Prepend (): Inside the existing element, insert the element from the front

The basic design idea and main usage of jquery